A technical history of the 19th-century electromagnetic telegraph, with special reference to the origin and variey of the alphabets, or codes, that were used.
This paper began as an investigation into the circumstances of the origin of the International Morse Code, and how it was descended from the American, or Vail, Morse Code. This was satisfactorily done, showing that the usual Morse Code was the adaptation of the original code to the requirements of the German language around 1851. The scope was then broadened into the early history of the telegraph in continental Europe, which is not well-known to British and American technical historians, and has consisted mainly of isolated references, erroneous dates and partial understanding. This revealed the important role of K. A. Steinheil as a telegraph pioneer, and, later, as a proponent of the Morse system in Europe. This led to an investigation of the actual contributions of Morse and Vail to the telegraph, and its early days, which has been considerably obscured by the just reverence for Morse as a man. To make this clearer, I decided to include the technical background for the electromagnetic telegraph, and to show how the various elements work together, and were realized in practice. Finally, having done this, it seemed interesting to trace the history of the telegraph in the United States lightly to point out the relations with railway operation, military communications, and other classic applications. As a result, this paper has grown to unwieldy proportions, and the various twists and turns may still be traced at certain points. Nevertheless, the index above will allow you to jump to any part you wish to consult, and the only real disadvantage is the time required to load the file. Its size, however, is still less than that of many graphics that may be put in your way!
The References include the works I have consulted, with notes on them, and recommendations for reading. I have not covered business or traffic matters except as they influence the technical considerations, but there are a few lines on labor relations and woman operators, a fascinating subject. I have also made much clearer how telegraphs came to be used on railways in the United States, I believe. I would greatly appreciate any notice of errors or misapprehensions. The paper is currently in course of revision, and some of the rough spots and relics of earlier versions you may notice will, I hope, disappear.
"Il arrache le sablier de la main du Temps, et efface les limites de l'espace" (duMoncel)
Alfred Vail watched as the register clicked out the first official message on the new government telegraph in the Pratt Street Station of the Baltimore and Ohio Railroad on the Baltimore waterfront, 24th May 1844. When it was complete, he stopped the tape drive, pulled the wedge out of his key, and tapped the message back to Samuel Morse in the Capitol Rotunda in Washington, 44 miles away, who was greatly pleased. This was not the first electric telegraph, not even the first electromagnetic telegraph, nor the first recording telegraph, but it was a momentous event for the Morse Patentees, and the opening act of a telegraph drama that would spread world-wide within a decade. The alphabet of dots and dashes that was used here would survive without change until the last train dispatching by Morse on American railways more than a hundred years later.
A few days later, on the 27th, the Democratic National Convention in Baltimore nominated Silas Wright for Vice President. The proceedings were being reported over the new telegraph, so when Wright heard this he immediately telegraphed back declining the nomination, which he did not desire. The Convention was incredulous, and did nothing until the telegram was confirmed by a messenger from Washington. Henry Clay's nomination by the Whig Convention in Baltimore on the 1st had been passed on to Washington over the yet incomplete line from Annapolis Junction by Vail. These events helped to introduce the new means of instantaneous communication to an astounded public.
The amateur radio operator still uses the Morse Code, and until recently it was current for marine communications, part of the International Code of Signals used worldwide at sea, and is still retained for emergencies. Everyone knows that SOS is ... --- ..., the conventional signal of distress, with things in threes. But Vail would be puzzled. He would send ... . . ... instead. The new code is similar to his, but somewhat different, with some signals reassigned, and some brand new, especially the numbers, which are totally different. How, where and why did this new code originate, and who was responsible for it? This article will explain all of this, as well as describing the early telegraph, which was different from its later and more familiar versions.
Vail's description of the new Morse system, which appeared within a year of the first trial, gives no hint of who was responsible for its various elements. He claims that Morse conceived the system on board the ship Sully in 1832, and that the system demonstrated in 1844 was the result of 13 years' development. In fact, there was a vast difference between Morse's first musings and the practical system of 1844, and it seems that Vail was, himself, responsible for nearly every detail, though he claims nothing. Morse did indeed fashion a code, but it apparently was nothing like the code of 1844, but involved wavy lines traced by pendulums, and a code book. I believe that the final code was devised by Alfred Vail (1807-1859), who described himself as "Assistant Superintendent, Electro Magnetic Telegraph for the United States." The word used for telegraph codes of this type was telegraphic alphabet at the time, so when I say alphabet I mean the telegraph signals for letters, numbers, punctuation and procedural signs. The word code strictly means a dictionary of messages indentified by numbers or some such means. Vail's Morse alphabet was called by Shaffner in 1859 the American Morse, and the now-familiar system the European Morse. These are excellent terms, but, unfortunately, they were not generally adopted by later writers.
Most sources, such as encyclopedias, have no reason to make a distinction, since they are not aware of any alphabet but the one familar to them, which is simply called the Morse Code. With few exceptions, all non-American sources give only the European Morse alphabet, called simply Morse. This alphabet has also been called Continental Morse, and more lately, International Morse. Vail's original alphabet is called just Morse in early American sources, and usually American Morse when a distinction has to be made. In this paper, I will usually call it the Vail Code or alphabet, and the other the Morse Code or alphabet, simply to make a clear distinction between the two.
Much of the history of the telegraph that is found in recent secondary non-technical sources is unreliable when it comes to the engineering and operational history of the subject. Many authors simply uncritically copy bits out of a technical source that they do not well understand, and nearly all have never operated a telegraph key or heard a sounder. (The sounder, the characteristic American telegraph receiver, is explained under Receiving By Ear.) For example, I noticed that an economic historian said the early telegraph used lead storage batteries. These weren't even invented at the time, and were later used only with dynamo power sources. It's no big point, but shows that otherwise reputable and well-researched accounts can fall short technically. The actual telegraph alphabets seem never to be mentioned in later histories of technology, and are not common even in early references. Thompson, in his excellent business history of United States telegraphs, even reconstructs Morse's first message with the International Code, using dot dash instead of dot dot..dot [p. 24]. He also explains the sounder as a "buzzer" [p. 250], and some of his statements about British and European matters are simply wrong.
It is interesting that communication once again is becoming dominated by telegraphy. This page reached your browser by telegraphy, and soon the crass, mindless rubbish of television will also reach you the same way, instead of through the familiar analogue links. Except for local subscriber circuits, telephones are already digital. The internet uses packet switching, unlike the circuit switching that came in with telephones, which is much more efficient and economical than devoting a link exclusively to one user. The alphabets and means of modulation are very different, however, and computers assume the roles earlier played by humans. Nevertheless, many old ideas, such as communication over light beams, have been resurrected. In fact, your television remote communicates by on-off telegraphy in a very familiar way.
The electromagnetic telegraph operates on a very straightforward and elegant principle. The transmitter opens and closes an electric circuit at one point. The receiver uses the electric current at any other point in the closed circuit to establish a magnetic field, the forces arising from which cause some observable mechanical effect. An electrochemical telegraph, such as the Bain telegraph, uses instead the chemical action of the electric current. Any other observable effect of the electric current could be used as well, provided it does not require an undue amount of current nor a too-high voltage. The heating effect has also been used.
Four scientific principles must be understood in order to create a useful electromagnetic telegraph. First, above all, is the production of galvanic currents by chemical action. This was demonstrated by Alessandro Volta in 1800, and the current was soon afterwards discovered to decompose water by electrolysis, and to heat fine wires. Chemical action in batteries was the only practical source of electricity for telegraphs until almost the end of the century, except for the occasional use of the magneto for intermittent currents. The second principle is the production of a magnetic field by a current, together with the means by which it can be intensified and caused to have a practical effect. G. D. Romagnesi of Trent seems to have been the first to observe, in 1802, that a current affected a magnetic needle, and a certan J. Majon observed that an unmagnetized needle near a current became magnetized. Such reports were little noticed until Oersted published his more detailed observations in 1820. Ampère then quickly worked out the magnetic action of a current, and Schweigger of Halle, in the same year, showed how to intensify its effect by winding the conductors in coils with the needle within, often called multipliers. The third principle is the temporary magnetization of soft iron. In 1825, Sturgeon wound the wire around an iron core and showed that this greatly increased the forces that could be exerted, showing the way to making strong electromagnets that would exert considerable forces on an iron armature. Finally, the requirements for designing an outdoor circuit of great length were established by Ohm (1827), Steinheil (1833)and Wheatstone (1836). This rested mainly on an appreciation of Ohm's Law, V = IR, and the meanings of electrical pressure and electrical current. Few of the earlier proposals for an electromagnetic telegraph got far enough to encounter the problems of a long outdoor circuit, which would generally have proved insurmountable. Indeed, the problem was not practically solved until after 1840, with the bare wire line supported by insulators on poles.
In 1845, few people had any idea of what an electric circuit was and how it functioned, and this included most of the telegraph pioneers, except for a few academics like Wheatstone and Steinheil. Ohm showed that the circuit was like the conduction of heat, with electrical pressure or voltage V, the driving force, electrical current I the flow or flux, and the resistance R the pressure needed for a unit flux, except that the analogue of heat had to flow in a closed path, like a fluid in a pipe with a pump. Hardly anybody believed him, but the analogy with a fluid was at least comprehensible, and is still used in explaining the electric circuit. Unfortunately, the analogy is a very poor one if carried any farther. Electricity was presumed to be an ethereal fluid like heat (also wrong) and this led to strange, useless conceptions.
Those who did understand Ohm took the pressure of the Daniell cell as the unit of pressure, the volt V, and a certain column of mercury the unit of resistance, the ohm Ω. The current forced through 1 Ω by 1 V was the unit of current, the ampere, A. Then, the current I in amperes through any part of a circuit is equal to the voltage V applied across the part of the circuit, divided by the resistance R of the part. In a complete circuit, the pressure rise in the battery, E, equals the pressure drop V in the rest of the circuit, so E = V = IR, which is Ohm's Law. Four Daniell cells, each providing a pressure of 1 V and having a resistance of 2 Ω will force a current I through 10 miles of #9 iron wire, with a resistance of 160 Ω given by I = 4 V / 168 Ω = 0.0238 A, or about 24 mA, milliampere. The electrical current stays in the wire, unless the wire touches some other conductor of electricity. All of the early books on telegraphy take extreme pains to make these facts clear.
The electromagnet, which can attract a soft iron armature when energized, and release it quickly when the current stops, is the essential element of the electromagnetic telegraph. Arago noted that electric currents made nearby iron needles magnetic in 1820. In 1825, William Sturgeon carefully inserted a horseshoe-shaped iron core in a helix of bare copper wire. When he passed a current through the helix, the core became a magnet. He then insulated some wire with cotton thread, which enabled him to use a greater number of turns, and get a stronger magnet. Sturgeon's electromagnets soon became a popular demonstration, and an informal competition on who could make the strongest magnet soon arose. Moll made a magnet that supported 75 lb, and then one of 135 lb. in 1828. Joseph Henry's 1829 magnet had a 2 in square core and was 20 in long, wound with 540 feet of insulated wire. Henry later made magnets that could lift 2063 lb, and then 3500 lb.
Early electromagnets were not all the same. Sturgeon, looking for strength, wound his iron with a relatively few turns of large wire, so that he would get the greatest current, which would be limited mainly by the internal resistance of the battery. The magnetic effect depends on the product of the current and the number of turns, and Sturgeon tried to maximize this product, as did most others. He also found that the greatest forces were produced when the iron formed a closed loop with only the minimum air gap necessary, which is, in fact, a closed magnetic circuit of low magnetic resistance. Such a magnet was totally unsuited for a long telegraph line of relatively high resistance that would allow only a feeble current. Telegraphs made with one would work in a room, but would fail completely to work over only a short line, as many telegraph enthusiasts found to their disappointment.
Joseph Henry, among others, made magnets with many turns of fine wire as early as 1831, maximizing this quantity instead of the current. Now many cells of battery could be used in series, since the current would not be limited by their internal resistance, but by the resistance of the winding around the iron, and only a small current could exert strong forces. Such were called intensity magnets, working with high voltages, rather than the earlier quantity magnets that worked with high currents. The use of such magnets was the necessary and sufficient condition for a practical electromagnetic telegraph, not a mere 'detail' as Morse would have maintained in his state of electrical ignorance. Electromagnets and their properties were well-known in the United States only a few years after Sturgeon's invention.
The terms "earth" (British) and "ground" (American) in telegraphy usually refer to an actual conductive connection with the damp soil of the earth's surface or to the sea. This connection was generally made with a buried copper plate, or in some cases to a connection with a metallic pipe in contact with the ground. The resistance of the earth return was negligible, if a proper earth was made, with a buried plate in moist earth. Telegraph circuits were almost exclusively ground-return, as they were not affected by noise, since they depended on on-off operation. This insensitivity to noise is still an advantage of telegraphy. Telephony rapidly found that it could not use the cheap ground-return circuit.
Telegraphs have a very ancient history. Polybius tells about letters displayed from towers, but visual telegraphs were quite impractical until the invention of the telescope in the early 17th century, and even then were not used for general messages until the remarkable Chappe telegraph of 1793, which gave us the name of telegraph. Before that, the world relied on messengers and beacons. Agamemnon sent information back to Mycenae of his victory at Troy by a chain of signal fires before 1000 BC, and beacons announced the arrival of the Spanish Armada in AD 1588. Romans used chains of watchtowers in the same way. American Indians used signal fires on hills as beacons, different numbers of columns of smoke indicating different messages. The messages had to be prearranged for this method to work. I do not know of evidence that Indians used smoke puffs with signal fires, but if they did, they certainly did not use the Morse Code for this purpose.
The electromagnetic telegraph spread with astonishing speed after its celebrated commercial introduction around 1845. By 1850 the United States and Britain had extensive networks, the telegraph was spreading to the European continent, having crossed under the Channel in that year, and by 1870 formed a world-wide telecommunications system. Indeed, it spread more rapidly than today's Internet. The optical telegraph was its only effective predecessor, and that mainly in France with the Chappe system, and a few lines for military and government messages in other countries. Chappe's optical telegraph dated only from 1794, and was for official messages only. Before that, there was no rapid communication at all, intelligence travelling no faster than a galloping horse. One reason for the success of the electromagnetic telegraph was its cheapness, speed and all-weather, all-day reliability (far superior to any messenger), but another was the radical change in society at the time, and the remarkable exploitation of the invention by private individuals and joint-stock companies in the United States and Britain, where it was enthusiastically accepted by commerce, newspapers, and the general public. Some of the earliest users were lottery men and stock brokers hoping to gain an advantage by timely, secret information.
Two systems of electric telegraphy achieved commercial success and fame, the needle telegraph of Cooke and Wheatstone in England (1839) and the recording telegraph of the Morse Patentees in the United States (1844). Both systems were the results of years of development, the efforts of predecessors, and the 'state of the art' in electromagnetics. The dates are those of the first commercial lines. These were by no means the first electromagnetic telegraphs, and neither system was a new invention, but simply the application of known principles to form a complete, useful system. Cooke and Wheatstone claimed only to have made an 'improvement' of the electric telegraph. The partisans of Morse claimed for him all originality and priority, quite ridiculously, and Morse, whose knowledge of technical subjects and electricity was negligible, soon firmly believed them himself. Even Alfred Vail, loyal associate of Morse, who actually invented the code and instruments that made Morse's ideas practical, was pushed into the shade as time passed. The unseemly and excessive pretense was carried on even by Morse's descendants. Let us, therefore, first look at the state of electrical telegraphy before Morse and Cooke.
Many inventors had tried to make telegraphs based on static electricity, but these were all impractical because of the difficulty of transmitting high voltages, and the weakness of the effects produced. Wood, in 1726, or Grey and Wheeler, in 1728, seem to have been the first to discharge a Leyden jar through long wires. In 1746, Winkler of Leipzig discharged a Leyden jar across a river. In 1748, Benjamin Franklin discharged a Leyden Jar through a wire across the Schuylkill River, igniting alcohol flares simultaneously on both banks, to the delight of the audience. He used only one wire, but this was not an anticipation of the ground return, since the concept of an electric circuit did not then exist. Dr Watson, bishop of Llandaff, constructed a static electricity telegraph on Shooter's Hill near London in 1747, 2 miles in length, after earlier experiments across the Thames at Westminster Bridge in London and at Stoke Newington. The mysterious C. M. (probably Charles Marshall of Paisley) suggested the speed of electrical communication in a letter of 1 February 1753. G. L. Lesage's static electric telegraph of 1774 in Geneva was one of the earliest actual devices to appear. It used one wire per letter, 24 in all, a pith-ball indicator, and only connected two neighbouring rooms (not shores of the lake). A similar demonstration is reported in France in 1784.
The Dyar telegraph of 1828 was an extraordinary episode. Harrison Gray Dyar proposed a telegraph between New York and Philadelphia using static electricity about 1826, and built a trial line around a race course on Long Island in 1828. He used bare iron wires on glass insulators with an earth return, producing the electricity by friction, and detecting it by its chemical effect on moist litmus paper, moved by hand. Fear of prosecution for "sending secret communications in advance of the mail" brought the project to an end. It would not have worked, because of leakage, but the attempt is remarkable in its anticipation of many later developments. Dyar had an alphabet of symbols, based on numbers of "dots." His work, and early telegraphic alphabet, had no influence on later developments. He is, however, heard from again in the patent litigation over the telegraph in the 1850's.
A certain Reizen is reported to have made a telegraph using static electricty in 1794 that used 76 line wires. Betancourt experimented in 1798 with a line from Madrid to Aranjuez. This is the same as the Spanish experiment by De F. Silva that used sparks from Leyden jars on a 26-mile line. The best-known and practical static electricity telegraph was that of Sir Francis Ronalds (1788-1873) in 1816 or 1823 at Hammersmith, London. The eight-mile line used synchronized clocks indicating letters, with a suspended pith ball as an indicator of what letter was meant. At least it did not have 76 wires. It is obvious that the idea of an electric telegraph was in the air throughout the 18th century, and there were many experiments, though no practical telegraph using static electricity was devised.
Current electricity, discovered in 1800, offered new advantages, but at first the only effect of the current that could be used was electrolysis. S. T. von Sömmering's telegraph of 1809 had 26 wires, each corresponding to a letter of the alphabet. Signals were received by noting which wire was producing bubbles. Schweigger of Halle used an alphabet of groups of bubbles to reduce the number of wires. Baron P. L. Schilling von Cannstedt, of the Russian Army, was very impressed by a demonstration, and thereafter collaborated with Sömmering on telegraphs. When the effect of currents on a magnetic needle became better known after 1819, Baron Schilling used suspended needles as a receiver. An early design had 36 needles and 72 line wires, but this was reduced later to a single needle. This was in 1820, and comprised the first electromagnetic telegraph. [A misunderstanding causes some authors to assume that this was in 1832, but the earlier date is correct. Reid gives 1836 for partisan reasons.] Dr. John R. Coxe of Philadelphia proposed a chemical telegraph with 72 wires in 1816, but never built one. Ampère experimented with a magnetic needle as a telegraph receiver in 1820, following a suggestion by Laplace. He clearly recognized the possibility of telegraphy by magnetic needles, as appears in his paper in Annales de Chimie et de Physique, v. 15, p. 72 (1821), suggesting one needle and wire for each letter. Ampère also was the first to use a key for breaking the circuit. In fact, he used many wires and a keyboard like a piano.
Gauss and Weber of Göttingen University became interested in the subject, and used the mirror galvanometer, which they had invented, as a receiver, employing polarized currents. That is, the direction of the current could be reversed, which gave an opposite deflection of the galvanometer. They constructed an alphabetic code using from one to four deflections to the right or left, which is shown in the Figure. Their circuit extended from the Physics Laboratory to the Observatory, a distance of 4500 ft, so the total length of the circuit was 9000 ft. This was in 1833. They had little time to spend on the project, so they enlisted the help of Professor K. A. Steinheil (1801-1870) of Munich University, with the principal aim of making a recording telegraph.
Steinheil, born in Elsass (Alsace), had come to Göttingen in 1823 as a student, and followed Gauss to Königsberg, where he received his doctorate in 1825. His specialty was instrumental astronomy. On the death of his father, he moved to Munich in 1830. He effortlessly became Professor of Mathematics and Physics in the University, and Conservator of the Mathematical and Physical Collections of Bavaria, in 1832, so capable was he. At the time of consulting with Gauss and Weber, in 1835, Steinheil was making a scientific journey through Vienna, Berlin and Göttingen. Professor Steinheil devised a receiver consisting of two bar magnets in a large, 600-turn coil. The magnets were pivoted so that one or the other moved when the current was in one direction or the other. Fine ink siphons were connected to the magnets, so that dots could be printed on a moving strip of paper, and a suitable alphabetic code was devised, shown in the figure. 
A bell alarm was included in the system, which could work at 6 words per minute (33 characters a minute). The main circuit was from the Royal Academy to the Bogenhausen Observatory (30,500 ft), but there were shorter lines from the Academy to the Physics Laboratory, and from Steinheil's residence to the Physics Laboratory. He also devised a magneto transmitter, which supplied currents by motive induction, not by chemical action. Any of these telegraphs would have been commercially viable, but Gauss, Weber and Steinheil were philosophers, not businessmen. Steinheil's telegraph was the first recording telegraph, clearly anticipating Morse on all counts. Steinheil's name should be added to those of Morse, Vail, Cooke and Wheatstone as an originator of the practical electromagnetic telegraph, something that even Morse later admitted.
Gauss had suggested that the two rails of a railway might serve as telegraph conductors. Steinheil followed up this suggestion on the Nürnberg-Fürth Railway, but finding that the rails were not sufficiently insulated from each other and the earth, even when felt insulators were used in the rail chairs. Through this, he serendipitously discovered the earth return, a great advantage for all telegraphy, which he declined to patent, dedicating it to the public. He constructed a line 4-1/2 miles long, connected to a buried copper plate at one end, and to a buried zinc plate at the other, evidently hoping for the galvanic action to also supply the current. This hope was impractical, but the earth return proved a very important invention. Not only did it make lines half as expensive to build, but also reduced their resistance and leakage to half. All this happened in 1837-8. Steinheil was the inventor of the lightning protector, in the form of a shunt around the apparatus, die Blizplatte, in 1846. He also invented a Translator [thus in German] to replace relaying by retransmission at intermediate offices. Steinheil devised a rheostat, wound with fine brass wire, for adjusting the current in a telegraph circuit, which varied with the weather. Steinheil also invented an electric clock (a master-slave clock arrangement), and in 1838 established an experimental train control telegraph on the Munich-Naunhof railway, that reported the progress of trains along the line. Steinheil also made the first Daguerrotype in Germany in 1839, developed electroplating and alcoholometry, besides working in the standardization of weights and measures for the Kingdom of Bavaria. Telegraph trials were also made on the Saxon State Railways between Leipzig and Dresden by Weber of Göttingen and Steinheil in 1838, applying the telegraph to train operation, says M. M. von Weber in 1867, who also claims (probably erroneously) that the earth return was discovered there. Nothing permanent came from all this activity, except additional knowledge, since telegraphs in Germany, as in all of Continental Europe, were a monopoly of the postal authorities.
Professor Muncke of Heidelberg set up a telegraph line of his own, based on Gauss and Weber's, between his residence and his lecture hall, which he demonstrated to students. One demonstration was seen by William Fothergill Cooke (1806-1879) in March 1836, and made a deep impression. Afterwards, Cooke worked only on telegraphs. He enquired of Faraday about how he could get technical assistance, and Faraday referred him to Professor Charles Wheatstone (1802-1875). He formed a partnership with Professor Wheatstone on 19 November 1837. Wheatstone provided the essential electrical knowledge, so the telegraph, patented in 1837, soon saw the light of day. Cooke's attention to its promotion as a railway adjunct, for the operation of single lines, soon saw it in commercial application in the same year, at Euston Station. Wheatstone was not only an extremely skilled inventor, but one of the few people at the time who understood Ohm's analysis of the electric circuit, a key factor in the later development of the telegraph. This is the chain of events leading to the Cooke and Wheatstone telegraph, which they described as 'an improvement to the electromagnetic telegraph,' not as a new invention. Though the two men later fell out, they were complementary to each other, and their cooperation was necessary for success.
The story of Morse's invention comes largely from claims exchanged by himself and Dr C. F. Jackson in a later battle over credit, so they must be taken with a grain of salt. Samuel F. B. Morse (1791-1872) was returning in Autumn 1832 from Havre on the Sully after a visit to France to copy paintings when he fell into conversation with Dr Jackson, who was enthused about Pouillet's powerful electromagnet that he had seen in Paris, and had a small electromagnet and battery with him (he said). Morse conceived that this could be the basis of a telegraph (thinking, he said, of Franklin and the kite--probably the only electrical thing he knew). Experiments in 1835 proved fruitless, so he applied for help to Dr Leonard D. Gale (1800-1883), who showed him how to build suitable electromagnets, on Henry's principles, and supplied him with wires and battery. Morse had been fumbling with Sturgeon 'quantity' electromagnets that had a winding of low resistance and used a single cell, and were totally unsuited to telegraphy. Gale introduced him to the 'intensity' electromagnets of Joseph Henry, which had high resistance windings made from many turns of fine wire, and were used with batteries of many cells. Such magnets were essential to telegraphy. Morse contrived a system in which magnets moved a suspended pendulum to which was attached a pen or pencil to make zig-zag lines on a paper tape in response to long and short impulses (the "pen lever"). The lines were interpreted as numbers, and the meanings of the numbers were looked up in an elaborate code book. The original Morse system was indeed a code, not an alphabet.
Joseph Henry (1797-1878) had, like Muncke, set up a demonstration telegraph in his lecture hall in Albany by 1830, and Morse came to him for advice as well. Vail omitted to credit Henry in his 1845 book, and Morse likewise neglected to give any credit for the essential help he had received. Henry, Professor of Physics at Princeton from 1832, and first Director of the Smithsonian Institution in 1846, was deeply insulted by the inventor's arrogance. In 1831, he had invented the "intensity" electromagnet of high resistance, and rang an electric bell at a distance using a relay. All the electrical parts of the telegraph were common knowledge before Morse ever thought of it.
After the subsequent commercial success and fame of the Morse telegraph, Jackson thought he could claim some of the credit, and made an uproar in the newspapers. Jackson was notorious for engaging in such activity; Morse was not his only victim. The very thought that a mere conversation aboard ship could possibly be considered as marking anything significant, or for which credit was due, was absurd. Morse, for his part, was completely unaware of the decades of previous work on telegraphs, and even claimed that Steinheil had stolen his ideas, when an account of Steinheil's work in a translation from an article in the Neue Würzburger Zeitung was published in the United States in 1837. Later, the Morse family even attacked the contributions of Alfred Vail, who was responsible for the actual design of the system called the Morse telegraph, including the key, register, and code. Vail concurred with using Morse as a trade name for the complete system, of course, since he was a partner in the syndicate, and well knew Morse's insistence on using the name Morse for everything involved. The two men were never enemies or adversaries.
Relations were much more cordial twenty years later, on 17 August 1858, when the telegraph authorities of France, Austria, Belgium, Holland, Piedmont (Italy), Tuscany, the Vatican, Sweden, Russia and Turkey awarded Steinheil a prize of 400,000 francs in Paris for his invention of the earth return, and a similar prize to Morse for his system. In his acceptance speech, Morse acknowledged simultaneous invention in America, Britain and Germany in 1837, praising Steinheil as noble, unselfish, great-hearted and modest (which he was), and acknowledging the leading role he had played in spreading the Morse telegraph in Germany. Morse's speech was published in Comptes Rendus de l'Acad. des Sciences, v. 7, p. 595 (1858).
Arguments over priority of invention of the telegraph arose almost at once, and had become quite heated by 1850. Most early observers concluded that the electric telegraph had no single inventor, an idea that seems very well founded. Practical electromagnetic telegraphy arose simultaneously in Germany, England and the United States at about the same time and more or less independently, but resting on a common foundation of technical knowledge that we have outlined above. It should be very clear that even before Cooke and Morse began promoting their telegraphs, the idea was by no means new. Both enterprises would have failed without the scientific and engineering contributions of Wheatstone and Vail, as much as without the business and promotion abilities, and tenacity, of Cooke and Morse. This is a remarkable parallel.
The fundamental Morse patent was granted 20 June 1840, extended 7 years in 1854, and expired 20 June 1861. An attempt to renew the patent again was rejected by Congress. The second patent expired 11 April 1860. The principles protected by these patents were well-known at the time, though not to American patent authorities or the courts. Only the details of the apparatus should have been protected, not the use of electricity and magnetism itself. Morse's patents were owned and promoted by a group called the Morse Patentees, which included S. F. B. Morse (inventor) 9/16 share, A. Vail (engineer) 2/16 share, L. D. Gale (scientist) 1/16 share, and F. O. J. Smith (1806-1876), a politician for legal and governmental liaison, 4/16 share. Amos Kendall (1789-1869), a lawyer and Postmaster in the Jackson administration, and Smith handled the business and patent affairs, Vail the technical side, Gale apparently did nothing whatever, taken on only to lend a scientific tint, while Morse took all the credit. Vail had received a quarter share on 23 September 1837, later reduced to an eighth to add Smith to the syndicate. Morse bought out Gale for $15,000 soon after. Shortly before the patents expired, the American Telegraph Company bought the remaining rights of Smith, Morse and Vail, and House and Bain to boot.
'Fog' Smith proved a difficult associate, but Amos Kendall became Morse's trusty business manager. Smith was a ligitious, disloyal, unlikable Yankee who later persecuted Henry O'Rielly for absolute control of the Morse patents in the West, reneging on a contract concluded with Kendall. The contributions of Alfred Vail were not clearly distinguished and documented. Unlike other members of the syndicate, Vail did not become wealthy or successful, probably because he did not blow his own kazoo loudly enough. Vail, who was intending to become a minister and was studying at the University of the City of New York, saw an early demonstration of Morse's there on 2 September 1837, and was fascinated. He was active for the Morse cause in 1837-38, then again 1843-48. He described the Morse system in his book The American Electro-Magnetic Telegraph of 1845, which set off the unpleasantness with Joseph Henry over lack of acknowledging his assistance, which was significant. Later researchers have given Vail more of the credit that is undoubtedly his due. Morse and Smith were masters of no effective electrical or mechanical knowledge whatever. Alfred Vail did not "improve" Morse's invention; he created a very different and practical system with Morse only observing on the sidelines. Without Vail (and Henry), there would have been no Morse telegraph.
Morse demonstrated his earliest device, with port rule and pen lever, on 2 September 1837 in New York, where it did not work, but Vail became interested, and offered to help. On the 4th it traced out the numbers 215 36 2 58 112 04 01837, which, translated by Morse's vocabulary, said "Successful experiment with telegraph September 04 1837." The impulses were sent by the so-called port rule, which had lead teeth like printer's type acting on switch levers that raised and lowered wires in or out of cups containing mercury as it was moved. The pulses were received by a pendulum deflecting to one side by the action of an electromagnet. The first code merely used from 1 to 10 pulses, each making a sidewise jerk of the pen. Later, the code shown at the left, devised by Morse, was used, which made short and long jerks. Vail was made a partner on the 23rd, and set to work improving the invention. An experiment over a half-mile of line was carried out on 2 October 1837, probably unsuccessfully. For the rest of the year, Vail worked to produce a different instrument, the register. On 6 January 1838, Vail's new register was tried over three miles of wire strung around the shop at Speedwell Iron Works in Morristown, New Jersey. Morse's memory later made this thirteen miles. The message sent was "A patient waiter is no loser." Soon after, the strange message "Attention the universe by kingdoms right wheel" [sic] was sent at a demonstration in New York City, probably on the 13th. On 8 February 1838, a demonstration was held before the Franklin Institute in Philadelphia, and finally on 21 February before the Congressional Committee on Commerce in the Capitol at Washington and President Van Buren. Reports of the Capitol demonstration were published in the American Journal of Science and Arts, v. xxiii, p. 168, and in the London Mechanics' Magazine for 10 February 1838. The chairman of this committee was F. O. J. (Fog) Smith, representative from Maine, who enthusiastically offered Morse his services, which were gladly accepted--provided he resign his government attachments to avoid conflict of interest.
By the time of the Capitol demonstration, Vail already had produced the new instrument, the register, that embossed dots and dashes on a moving paper tape by a stylus operated by an electromagnet, the circuit being opened and closed by a manual key. A later version is shown at the right. The key was used for winding up the weight (not shown) that drove it. The register worked much better than Morse's original pendulum contraptions. Morse could see no difference, but an idea is not an invention, and Vail had taken the essential step of reducing the invention to practice. The essential new element was the large electromagnets with many turns that required only a small line current. One of the greatest advantages of the Morse system over its competitors proved to be its production of a permanent record of a message, which other telegraphs (as far as Morse knew) did not do. Steinheil already had a recording telegraph, however, which operated like Morse's. This was the factor largely responsible for the spread of the Morse in Europe, where the Cooke needle telegraph was never widely used. Vail also devised the telegraph alphabet that came to be known as the Morse Code (with Vail's agreement) for use with the register. Part of an early form of the alphabet, superseded by 1844, is shown at the left below.
F. O. J. Smith was taken into the partnership for his political knowledge and influence. He financed Morse's visit to England, and accompanied him there (where they found that their inventions had been anticipated) in 1838. The pair returned somewhat miffed if not chastened, but aware that their's was not the only telegraph in the world. Through Smith and persistence, Morse finally succeeded in getting a federal subsidy of $30,000 by an Act of Congress in 1843, which made possible a 40-mile demonstration line between Washington, DC and Baltimore, over which the first public message was sent on 24 May 1844. This message ("What hath God wrought") was composed by Annie G. Ellsworth (or Elsworth), the daughter of Mr Ellsworth of the U. S. Patent office, a friend (and partisan) of Morse's. The tape was given to Governor Seymour of Connecticut, and is preserved in the Museum of the Historical Society of Hartford (Connecticut). It shows that the Vail alphabet was already in use. Morse was in the Capitol, Vail in Baltimore, and the message was sent and returned. The subsidy had reignited Vail's interest in the project, which had flagged after 1838, and he returned with enthusiasm. The US Post Office, to which Morse had offered the invention for a quite reasonable $100,000, stupidly failed to take it up, and so this was the only telegraph line built with federal aid in the United States. Private investors, especially the new Magnetic Telegraph Company, which licensed the Morse patents, eventually found the business lucrative.
Morse intended to bury the telegraph line, and Smith contracted to do this with a digging machine of his own invention. Smith soon enlisted the help of the technologically more capable Ezra Cornell (1807-1874) whom he had met earlier in Maine. Cornell devised a better digger, and began laying the wire in pipe (lead-sheathed cable) beside the Baltimore and Ohio from Pratt Street Station to Relay, intending to follow the Washington Branch thence to the capital. President Louis McLane of the B. & O. had given Morse permission to use the right-of-way as a personal favor. The cable had been laid as far as Relay when it was discovered that insulation failure had made the line useless, a disaster to the project's timetable. As an excuse for an extension of time to retain the subsidy, Cornell conveniently wrecked his digger, giving Morse the excuse he needed. It was decided to run the line on poles with Cornell's plate glass insulators (as Joseph Henry had suggested many years before), not Vail's cotton and beeswax. The conductors were #14 copper, wrapped with cotton thread and coated with a mixture of asphaltum, beeswax, rosin and linseed oil to keep the electricity in. The wire already insulated for the pipe was ready to hand. Two conductors were used for the circuit, instead of the earth return that had been introduced by Steinheil seven or eight years previously, and was already widely used elsewhere. This line clearly displayed the technological immaturity of the early Morse telegraph, but Vail and Cornell worked feverishly to refine it.
The first line had five Grove cells in Baltimore (keeping these evil things out of the Capitol and out of sight), and a key and register at both termini. Reid says there were 100 Grove cells in the battery, but this is probably incorrect, although large numbers of cells were soon used in attempts to drive unresponsive magnets. Before the public trial, Vail had made copper ground plates, 5 ft long by 2-1/2 ft wide, one of which was immersed in the sea at the Pratt Street docks, the other buried in the cellar of the Capitol. The ground return replaced the West wire for the duration of the trials. Afterwards, the keys and registers were rearranged so that transmission could simultaneously take place in both directions, using both wires. Vail was quite proud that only one set of batteries was required to operate both lines. The line was opened to the public on 1 April 1845, with Vail as operator in Washington, and H. J. Rogers in Baltimore, about a year after the first trial.
The register used for the trials embossed the paper tape with a steel point. Vail had first used a pencil, which required too much sharpening, then a pen, which kept clogging, then a method used for making manifold copies at the time (?), before deciding on the steel point. The paper factory made rolls 3' 6" wide on a wood core. These were marked off in 1-1/2" widths, and cut on a lathe with a knife, making 28 15" diameter rolls of tape from each large roll. The register was driven by a falling weight, which turned a clockwork regulated by a 'fly,' a primitive but effective means of controlling the speed. The first impulses received by the register would set the clockwork moving. The transmitting operator waited a short while until the register got up to speed, then transmitted his message. The receiving operator had to turn off the clockwork when the message had been received. The automatic nature of this is remarkable, and was very convenient.
The Morse inker was invented by Thomas John, an Austrian, in 1854, with the aim of making the register more sensitive. In this device, a rotating ink wheel dips in an ink reservoir. When lifted by marking current, it contacts the paper tape and leaves a mark. The most-used inker was manufactured by Siemens and Halske in Berlin, and was used throughout Europe. The paper tape was about 1 cm in width. Embossers remained standard in the United States.
The key used for transmitting was different from the later typical Morse key with front and back contacts, as well as from the modern key with a single contact pair and switch. It was a simple piece of spring brass with a 'hammer' and 'anvil' as the contacts were called at the free end. When it was desired to receive, a wedge had to be put between the contacts to close the circuit, allowing the operator at the other end to transmit with his key. This inconvenience was avoided by Vail's use of two wires, each used in one direction, so the key could be left open at all times. A new kind of key was soon designed, that would keep the circuit through the register closed, unless the battery was connected to the circuit by pressing the key.
When the Morse register was used, the circuit had to be normally open. To arrange for this, the key had both front and back contacts. When depressed, the key connected the battery to the line, at the same time disconnecting the local register. The figure at the right shows an elementary Morse-Vail telegraph station, such as would have been used in the United States in the 1860's. It shows an inking register, which replaced the embossing register. The register was usually operated by a relay, not directly from the line as shown in the Figure. Relays will be explained in detail below. They permit a feeble current to control a stronger one by opening or closing contacts. Morse independently had the idea of a relay, which he conceived as a repeater to operate very long circuits, but its practical use was for operating heavy-current devices like the register in a local circuit. Repeaters were not devised for many years, so messages were relayed at intermediate stations by retransmission. The noise of the register turning on served as an alarm to attract the attention of a receiving operator. A message could be sent, of course, without an operator being present to receive it, since the tape started automatically. The familiar later forms of the key, sounder and relay had been introduced by 1870.
The account I have just given of the beginnings of the Morse telegraph has been assembled from several sources, and seems to me to be relatively accurate. Nevertheless, the sources differ somewhat in dates, places, and names, even for the date of the 1844 event. May is probably correct, not March. A Dr Fisher is also said to have worked on the project, but no other reference to him can be found. However, there was a Dr Finley, Morse's uncle and the Charleston resident whose miniature portrait, painted by Morse, launched his painting career. Gale appears only to have shown Morse the Henry 'intensity' magnet he needed instead of the Sturgeon 'quantity' magnet, but this was a critical point that Morse never appreciated, and the change was made by Vail. Morse heard lectures on electricity by Jerimiah Day and Benjamin Silliman at Yale before he graduated in 1810, visited Silliman in New Haven in 1824, and heard James F. Dana's New York lectures where a Sturgeon-type electromagnet was demonstrated, in 1826 and 1827. Morse apparently never gained a useful knowledge of electricity, though he did not know significantly less than most of his contemporaries.
Companies were organized, funds raised, and construction begun in the latter half of 1845, with Philadelphia as a base. The Magnetic Telegraph Company was open to New York (Fort Lee, New Jersey) on 20 January 1846, and to Baltimore on 5 June. F. O. J. Smith's New York and Boston opened at Boston on 27 June. The New York, Albany and Buffalo reached Buffalo on 3 July, and the Atlantic, Lake and Mississippi Valley (later the Atlantic and Ohio) to Pittsburgh on 29 December. Except for Smith's Boston line, which aroused public scorn (Smith did not believe in insulation), these lines were in service more often than not. The original government line was purchased and went to the Magnetic. The winters of 45-46 and 46-47 taught many lessons in line construction. Copper soon disappeared, along with the worst of the insulation methods. All these lines were Morse lines, and more or less affiliated through the Patentee's interests. They followed railways on a few routes, but mainly struck out along common roads. Funds were difficult to raise in the coastal cities, so Rochester, Utica and other small cities took the lead. Initial public traffic was less than anticipated, and business was slow to increase.
John Butterfield of Utica, a stagecoach operator, had glimpsed the possibilities of the telegraph when he observed the government line on a visit to Washington, and obtained patent rights in early 1845 for the New York, Albany and Buffalo Telegraph Company, which he and his associates formed. This turned out to be one of the best and most reliable lines in the country. In 1847 it was extended from Buffalo to Montreal by a Canadian company. Smith's Boston line was extended to Portland in that year, eventually reaching Halifax through a chain of companies for the European news. The Washington and New Orleans Telegraph Company, promoted by Amos Kendall, who as postmaster had established an extra-charge express mail to New Orleans, built the long line through Richmond, Wilmington, Charleston, Montgomery and Mobile to New Orleans, completed in 1848. Soon, the only states east of the Missippi that did not have a telegraph line were Vermont, Tennessee and Florida. It should be remembered that in 1840, the population of Cincinnati was about 46,000, Pittsburgh 31,000, Louisville 21,000, Detroit 9100, Cleveland 6100 and Chicago 4470.
Henry O'Rielly (he spelled it thus; most references, including Reid, write O'Reilly) of Rochester contracted in June 1845 for the western rights to the Morse patents through the Pittsburgh gateway. He had met John Butterfield on the night boat to Albany on 7 January, and had become interested in the telegraph. His contract granted much of the territory also assigned to Smith when the Patentees divided their interests geographically. Smith tried, with only limited success, to declare the contract void the next year when he discovered what had been done. O'Rielly built the line from Lancaster to Harrisburg within the contractual time limit, but Smith claimed, unjustly, that it had to have been built through to Philadelphia within the time limit. The contract was not crystal-clear, but this was a very unfair accusation. Judge Kane of the U. S. District Court in Philadelphia ruled that he had not breached his contract. O'Rielly went on to build lines to Cincinnati, Louisville and St. Louis in the next few years, and even tried to extend his system beyond the limits set by his contract for the use of the Morse patents, with the People's Telegraph from Louisville to New Orleans. Smith, nevertheless, competed fiercely and relentlessly for more than a decade, building competing lines from the Buffalo gateway, which he controlled. O'Rielly was ruined in the end, though he had public support, and his lines were absorbed into Western Union together with Smith's in 1856.
As a contractor, in 1845-46, O'Rielly built the lines from Philadelphia to Baltimore and Pittsburgh. The Lancaster-Harrisburg line was opened in November 1845, the first commercial line (excluding the government line) to handle traffic. This company employed David Brooks, Anson Stager, C. T. Smith, and James D. Reid at the start of their telegraphic careers. The Pittsburgh line went from Philadelphia via Lancaster, Harrisburg, Carlisle, Chambersburg and Bedford to Pittsburgh, beside the railway from Philadelphia to Chambersburg, and beside the common road (now U.S. 30) beyond. When the Pennsylvania Railroad was complete, in 1853, the main line was moved to its right-of-way.
Messages were sent across the Hudson from Fort Lee by messenger or pigeon. Early attempts were made to cross this gap with cables, and by long aerial wires on masts, by various of the Morse associates, but with little luck. These people may have tried valiantly, but they certainly did not succeed, in underwater telegraphy. A successful cable was finally laid when gutta-percha insulated cables became available after 1847, the technology coming from Britain. This is discussed below in Underwater Telegraphs.
Amos Kendall became the business agent for Morse and Vail, while F. O. J. Smith exploited his quarter-interest separately. Kendall took the South, Smith the North. Competition ended with the formation of Western Union in 1855, in which the New York and Mississipi Valley Printing Telegraph Company of Rochester, New York, which was absorbing O'Rielly lines, merged with Smith's Erie and Michigan Telegraph Company. This company began eating up all the small, independent companies, and grew into a monopoly by the 1860's. Morse actually thought the telegraph should be operated by the Post Office, as it was everywhere except in the United States and Britain. British telegraphs, largely a monopoly, passed to the General Post Office in 1870, however, and the change was, in general, beneficial. In the U.S., the alternative of a regulated monopoly was chosen instead. It is curious that many of the American telegraph entrepreneurs were associated with Rochester, New York. Investors in the large coastal cities were not interested.
The year 1846 was the one in which many American telegraph pioneers entered the field, forsaking earlier occupations. Ezra Cornell manufactured telegraph instruments for Morse lines. In cooperation with F. O. J. Smith, Cornell, with his associate J. J. Speed, formed the Erie and Michigan Telegraph Co. to build lines from Albany north to Canada, and west to Milwaukee, which was reached in 1848 in the assault on O'Rielly's interests. In the same year, he organized the New York and Erie Telegraph Co., in effect competing with Morse and Vail, who had interests in the New York, Albany and Buffalo line. His empire entered financial difficulties, but an amalgamation of his interests with the New York and Mississippi Valley Printing Telegraph Company, a House line, created the Western Union Telegraph Company, as we have already noted, and rescued Cornell's fortune. After this, Cornell retired to found Cornell University in 1868.
By 1851, there were 67 Morse lines extending 20,000 miles, 8 House lines for 3000 miles, and 7 Bain lines for 2000 miles (see below for a description of the competing House and Bain telegraphs). The Mississippi River was crossed at St Louis by telegraph cables strung from high masts in 1852-3. The telegraph reached San Francisco in 1861. The speed at which the telegraph was extended in the United States was remarkable, but most of the lines were of execrable quality. By 1866, when the Atlantic Cable was put into service, most principal lines were in the hands of Western Union and the American Telegraph Company, who soon merged. The availability of money after the Civil War, and the low cost of telegraph construction, led to the mushroom growth of competitors, but there was little such competition after 1881, and Western Union dominated the market from then on. Some of the competing lines built after the Civil War were built solely for the purpose of being acquired by Western Union on advantageous terms.
The first telegraph customers were lottery sharps and stock brokers who obtained advance secret knowledge, of lottery numbers or the Philadelphia stock exchange, to gain advantage. However, news organizations were soon the best customers. Dispatches from the Mexican War were specially important, the earliest examples of instant news from the fronts. Newspapers formed associations to share intelligence, and obtained special volume telegraph rates. Six New York newspapers cooperated by forming the Associated Press for sharing the cost of news received by telegraph. It was much better than the postal service, which still used riders and saddlebags for most routes. Presidential annual messages were notable traffic: the first was President Polk's, in December 1848. It was attempted to send this message to many points by a single manipulation, and this almost succeeded, but a bitter storm made some relaying of the long message necessary. Soon merchants and businessmen found the wires essential for price reports, making deals and ordering. Private individuals began exchanging important messages, but did not use the service for chatting. A telegram was not cheap; a typical rate in 1846 was $0.25 for 10 words for 100 miles, exclusive of address and signature. This was a fourth of a skilled man's daily pay. In fact, early telegraph traffic was unexpectedly light, because of the high charges. Private telegrams became associated with disasters and sad news. In 1866, Western Union charged $2.05 for 10 words, New York to Chicago. In 1884, the charge was $1.00 maximum between any two points on the continent. Occasionally, ruinous competition reduced rates to unremunerative amounts, while rates on the Pacific telegraph and similar monopoly circuits were extortionate. There was little rationality in the rate structure.
Telegraph charges were based on the number of words, exclusive of addresses and similar information, distance, and priority. The tariffs, however, were inconsistent and chaotic while there were competing companies, and no good system for the apportionment of revenues was devised. Air line distance between source and destination replaced wire distance. Rationality was finally introduced by Western Union when their territory was divided into zones, and rates set on a zone-to-zone basis (like some parcels rates are today). This was only possible because Western Union held a virtual monopoly. Words in a message were actual words, not the arbitrary 5-character words used to specify speeds of transmission. Some newspapers thought of packing as much as possible in a word, with things like "retackmentativeness" or "rehairoringed" that could be expanded into a paragraph by a code. This practice was forbidden, and code (cipher) messages charged in some fair way where they were allowed. Early operators occasionally guessed at words when the lines were bad, with sometimes comic results, so the redundancy of plain text was welcome.
The idea of a telegraphic alphabet was not new with Morse or Vail. However, most telegraphic systems, before the electromagnetic telegraph, used large vocabularies of prearranged messages identified by numbers or some similar means, called a code. For example, the Chappe visual telegraph showed 196 different positions or symbols (of which the operators at intermediate stations did not know the meaning). The prearranged messages could be complete sentences, phrases, individual words, or even letters and figures. Which dictionary was to be used was also expressed in the message. Morse's original system was like this, transmitting numbers that keyed into a vocabulary. These messages included the letters and numbers so that unusual words could be spelled out, but the bulk of the traffic was to be handled by means of the code book. Alphabetic codes were early used in nautical applications. The coloured naval signal flags now denote letters and numbers, and the Pasley semaphore telegraph of 1822 also used an alphabetic code. The idea of an alphabetic code was, therefore, not new in the 1830's. As we have seen, Gauss and Weber, Steinheil, and others, had used alphabetic codes. Even using an alphabetic code, one frequently employs certain prearranged messages, such as the radio Q signals (for example, QSL -- 'please acknowledge this contact in writing'). These standard international signals are used in Amateur Radio, for example.
Vail took the frequency with which the different letters were used in English text into account, making the more used characters shorter than the less frequent ones. One source says that his brother George, a newspaper editor, contributed the data, but I can find no evidence of such a brother. Another source, which gives Morse the credit, says a brother was involved as well. Morse indeed had a brother (at least two, in fact), one of which collaborated with him on various inventions, but his biography gives no hint of any contribution to a code. A look at a printer's type font would give a very good idea of the frequency with which letters are used, in any case. Vail's code involved not only dots and dashes, but spaced letters (such as O, . .) and short, medium and long dashes. The T is a dash of the length of 2 dots, the L of 4 dots, and the 0 of 6 dots. These made sounds easily distinguishable on the sounder, which was ideal for receiving them, though the code preceded the sounder by some years. The Vail code turned out to be very well adapted to aural reception, though it was designed for the register. The use of the sounder in the United States ensured the continuation of the Vail code until its final use in railway train dispatching in the 1950's. There are many good reasons why it continued in this application even after the telephone was widely available, and was finally discontinued only because of a lack of Morse operators.
The European or Continental alphabet consists only of dots and dashes of one length, with no spaces in letters. O is - - -, for example. The International Morse O takes 11 unit times to send, the Vail O only 4. Vail tried to make the frequently-used letters as short as possible. The very common e is simply . , i is .. , t is -, c is .. . , and so on. In Morse, some of these carefully designed codes are greatly lengthened, as we have seen with O. C is -.-. , 11 dot times instead of 5. We will see that the changes were due to the adaptation of the alphabet to the German language, where, for example, C is much less used than in English. Numbers are much longer in Morse than in Vail. Indeed, abbreviated numbers are sometimes used in International Morse. It takes longer to send a given message in Morse than in Vail. Several dot-dash codes are shown in the section on Alphabetic Telegraph Codes to show the evolution of the Morse Code. Please consult this table when these codes are discussed in what follows.
Enthused by Muncke's demonstration, Cooke first tried to make a 'musical snuff box' telegraph, then one with an electrically-released escapement, both rather impractical. Wheatstone provided some new ideas, and Cooke thought of using electric currents to deflect pointers to right or left so that they would point to the letter to be transmitted. The already familiar magnetized needle in a coil of wire or multiplier was the means. This needle was connected by a shaft to the visible needle on the front of the instrument that was observed by the operator. The signals were sent by a commutator operated by a handle. When the handle was vertical, the circuit was open and the needle stood vertical. When the handle was moved to one side, a current was sent that deflected the receiving needle. When the handle was moved to the other side, the direction of the current was reversed, and so was the deflection of the needle. Five needles were placed in a row at the centre of a lozenge-shaped dial. Any pair of needles, when deflected, pointed to a single letter above or below the row of needles. This five-needle, or hatchment telegraph (from the shape of the face) instrument was to be connected with its mate at the other end of the line by five buried wires.
This telegraph was practical, and was actually brought into commercial service in 1838 beside the equally new Great Western Railway from Paddington to West Drayton, and eventually to Slough. The buried conductors, however, proved very expensive and troublesome. Although the early experimenters had used aerial lines with complete success, both the Cooke and the Morse telegraphs were introduced with buried conductors. The reason for this was not only to remove unsightly wires from public view, but also as an aid to security from physical damage or malicious interference. At Isambard Brunel's suggestion, the Cooke and Wheatstone line from Paddington to Slough was placed in iron pipe. However, the insulating materials of the day deteriorated rapidly under the conditions of burial, and lines soon became leaky and useless. Very soon, all telegraph lines were bare wire supported on insulators in pole lines. It was really not possible to make good buried cables until the introduction of gutta-percha insulation around 1847. Gutta-percha, a relative of rubber but not elastic, deteriorates rapidly when exposed to air and light.
As an example of the kind of misunderstandings that can arise in the history of the telegraph, Prescott says that the first electric telegraph was that of Wheatstone between London and Birmingham in 1835. He was using du Moncel as a source on telegraph history, and repeated an erroneous statement. Of course, the first Cooke and Wheatstone telegraph was between Euston Station and the Camden enginehouse on the London and Birmingham Railway in 1837, and was only an experiment, soon replaced by a pneumatic speaking tube.
Even with aerial lines, the five wires required for the hatchment telegraph were unnecessarily expensive. The number of needles was reduced to two or one, and the number of wires correspondingly. The simplified instrument case then acquired the familar Gothic form (but sometimes was a plain rectangular box with writing desk), recalled in the Philco radios of the 1930's, as shown below. The needles and handles were electrically and mechanically separate in the two-needle instrument. Since the needles could no longer simply point to a letter, some code had to be created out of the elementary signals of right and left deflections. The single-needle code used from one to four deflections for each character. The deflections represented by long lines were done first, and those represented by short lines last. For example, d is left then right, while r is right then left. The symbol that looks like a Maltese cross was called STOP. It was sent at the end of each word. The receiving operator then replied with a single deflection to the right (M) if he understood the word, but with STOP if he did not. Special letters were used to shift in and shift out of numerical mode. The code was printed on the face of the instrument. Wheatstone provided an alarm bell for attracting the attention of the operator, in case the rattling of the needle was insufficient.
The two-needle telegraph was intended to speed up transmission by employing the additional signals that could be sent by two needles used individually, or simultaneously. The needles were used individually to send the letters printed above them to right and left, using the appropriate number of repetitions. The code is shown on the right. The two-needle telegraph was the one mainly used for the commercial telegraphs, with trough batteries, in the 1850s and 1860s. The Electric Telegraph Company was formed in 1846, acquiring the Cooke and Wheatstone patents. By 1869, the needle telegraph was dying out as first the Bain electrochemical receiver, then the Morse register, then acoustic reception with the sounder, and finally the Wheatstone automatic telegraph took over. The single-needle telegraph remained as the normal 'speaking telegraph' on railways, where the demands made on it were not severe, and its cheapness and reliability were great advantages. It was still in use to an extremely limited extent as late as 1971. The single-needle telegraph was adapted as the three-position block indicator, and in this form survived into the 21st century. The block bell is a Morse key transmitter with a single-stroke bell receiver operated by a relay. Such instruments were used to a very limited extent in the United States in the late 19th century.
Needle telegraph receivers were essentially galvanoscopes to detect the presence and polarity of currents. The small permanent magnets not only became weaker with time, but strong earth currents in the coils could demagnetize them, or even reverse their magnetization, so they would give the opposite indication to the one desired. Every office had a large permanent magnet for remagnetizing the needles. This annoyance was relieved by the invention of the induced needle that used a sturdy permanent magnet to induce the proper polarity in a soft-iron armature connected to the indicating needle. Around 1866, C. V. Varley and C. E. Spagnoletti both devised induced needles.
Needle telegraphs were open-circuit in the sense that normally no current flowed in the line, and the needles were vertical (in the absence of earth currents). However, the circuit was closed through each instrument by contacts that opened when the transmitting handle was moved right or left, an action that put the local battery on the line with one polarity or the other. All needles on the line responded at the same time, and any operator could "break" by holding his handle to one side or the other. Exactly the same thing occurred when operating with a sounder, but the key had to have both front and back contacts, the back contacts keeping the line closed when not sending. In any case, there had to be a local battery for the line. Even when working a sounder, English circuits were operated open-circuit, and a needle was generally put in the line as a galvanometer. The usual line current was 15 mA.
By 1878 the Morse Code in its later form was used with the speaking telegraph on the Great Western Railway (and probably generally). Polarized currents were used with a single needle, as usual. Deflections to the left signified dots, those to the right, dashes. A full stop (period) was \\ \\ \\, 'I understand' was T (/), and 'I do not understand' was E (\). T was the response after the receiving operator took time to write down the word that had just been transmitted. It appears that the needle was watched until a word had been sent, and then there was a pause while the word was written down and acknowledged. Numerals were preceded by FI and followed by IF. The prefixes SP (important) and DG (danger message) were used to establish priority. When broken, the operator transmitting would send WQ ('I am in the middle of a message') and could proceed unless the operator breaking in sent DG. TA identified a train report, and S a public message. RT was the abbreviation for 'right.' The heading of this page shows a single needle sending the word "MORSE" with a left deflection for a dash, a right deflection for a dot [this is opposite to the usual convention; the graphic will be changed when time allows].
The Magnetic Telegraph Company, incorporated in 1852, operated lines from London to Ireland, over a submarine cable from Donaghadee to Portpatrick, and connected the major Irish cities, as far as Limerick, Killarney and Cork. The double-needle telegraph of Henley and Forster, with modifications by the Bright brothers, was used, which employed momentary currents generated by magnetos instead of batteries. The Brights were secretary and engineer of the company. Some of the lines of this company were underground. It also had lines to Glasgow and Edinburgh, as well as to Birmingham, Liverpool and Manchester.
Du Moncel classifies telegraphs as: writing, needle, dial, printing and autographic. All types except the last, which was a curiosity, were commercially used at some time. An autographic telegraph reproduces the movements of a stylus remotely.
The success of the Morse telegraph in the United States, and of the Cooke and Wheatstone telegraph in Britain, caused many inventors to work on telegraphs that could evade the patents which were being used to create monopolies in both countries. An early and important example was Alexander Bain's chemical telegraph of 1846. This was an improvement on the original 1839 chemical telegraph of Edward Davy. The novelty was the receiver, consisting of a disc of paper moistened with a potassium ferrocyanide and ammonium nitrate solution and resting on an iron plate, on which a stylus traced a spiral as the iron plate was turned by clockwork. Whenever a current flowed, and only a very small current was required, electrolysis caused the formation of iron ferrocyanide, or Prussian blue, and a mark was made on the disc. It looked much like a disc record player of many years later. Bain even constructed a new code of dots and dashes which was purposely different from the Vail (Morse) Code. At least one Bain character found its way into the later Morse Code, as well as his numbers, and there is a logical reason for this. Unlike the Morse register, the Bain receiver was completely quiet, so Bain needed some kind of alarm, and he devised one as far from looking like anything Morse as could be. Later Bain telegraphs used a paper strip instead of the disc, and an iron stylus instead of the iron plate. Potassium iodide could also be used as the chemical, in which case electrolysis would free iodine, and make a brown stain instead of a blue one. Bain originated automatic sending with a perforated paper tape in 1846. Apertures in the form of dots and dashes were made in the tape, which was run between a conducting brush and roller. Electrolytic reception can be very fast, since there is no mechanical or electrical inertia. However, the inconvenience of maintaining a moist tape led to its disuse. The Bain system also included an electromagnetic "call" device, necessary to tell the operator when to start the receiver, since otherwise the system was silent. These appurtenances were attacked by the Morse Patentees quite vigorously.
The Bain telegraph was introduced to the United States by Henry O'Rielly when the "Columbian" telegraph of Zook and Barnes (1848) was struck down in the courts as an infringement on the Morse patents, and negotiations to use the House telegraph (which would not have worked on his bad line anyway) failed, as he struggled to bring the Louisville-New Orleans People's Telegraph into operation. O'Rielly could use the Morse patents only within the territory assigned in his original contract. For all further expansion, he needed another system. Bain's system with tape transmission and chemical reception, and indeed a new alphabet, was enough unlike Morse that it was ruled by the Kentucky courts as no infringement. This line was an operational and financial failure until sold to others. In 1850, the important routes from New York to Boston, Buffalo and Philadelphia all had competing Morse, House and Bain telegraph lines. In that year, of 22,000 miles of telegraph line in the United States, 12,000 were Morse, and the rest were Bain and House.
The Vermont and Boston Telegraph Company adopted the Bain system in preference to the Morse when it was founded in 1848. It used the Bain system until after it was acquired by Western Union in 1866, when Morse instruments were substituted. It was probably the last Bain line in service, and a rare one in that it did not parallel a Morse line. The Bain telegraph was quite practical, but it lacked acoustic reception, and this proved a worse defect than the dampness of the solutions. The V&B used the English sand battery, #8 black Swedish iron wire, and the patent insulators of its engineer, Prof. Benedict, at least at the beginning.
The printing telegraph invented by Royal E. House of Vermont was patented in 1846, but was not usable until modified to eliminate interference with the Morse patents, and was repatented in 1852. It was the first printing telegraph, which recorded the message in ordinary letters on a strip of paper. The first U.S. patent application was attacked in court because of infringment of the Morse patents, after which House replaced electromagnets by pneumatic actuation. The operator worked a treadle to supply the air, and held down a key, like a piano key, that corresponded to the letter he desired to transmit. A commutator was rotated that sent pulses down the line, and the key operated a stop that stopped the commutator after the required number of pulses was sent, the number depending on the letter that had been sent last, so that a maximum of 28 pulses were required for each letter. There were 26 letter keys, and two more for "dot" and "dash." It is impossible to describe the mechanism adequately in the space available here, so the reader is referred to Jones or Prescott. At the other end, the type wheel or basket was rotated synchronously by pneumatic means as the pulses were received. When it stopped, the operator there took an action that pressed the receiving tape against the inked type, again using the air provided by a treadle. The first use was in 1847 between Cincinnati and Jeffersonville (Louisville). This was only a temporary expedient when Morse instruments were in tight supply. House circuits wer established by Downing between New York and Philadelphia, and New York and Boston, in 1849, and set off the court suits. 30 Grove cells were required for the 100 miles to Philadelphia. The House telegraph required a much better circuit than the slower Morse register did. In Britain, the House telegraph was known under the name of Jacob Brett, who was the representative there. The House was the fastest telegraph available at the time, twice as fast as Morse or Bain, but it required a good circuit and skilled operators. The air supplied by the treadles was later supplied by a crank turned by a man called the 'grinder.' Although the House telegraph saw much use along the Atlantic coast, it was generally adopted in the west when necessary to avoid the Morse patents. As soon as Morse patent rights were acquired, the House instruments were replaced by the much simpler Morse key and sounder.
The three significant early suits in U. S. District Courts were Morse vs O'Reilly, heard by Judge Monroe in the District of Kentucky, over the Zook and Barnes invention; Smith vs Downing, heard by Judges Levi Woodbury and Curtis in Boston over the House telegraph on the New York-Boston line in 1850; and French vs Rogers heard by Judge Kane in September 1851 in the Eastern District of Pennsylvania over the Bain telegraph on the New York-Washington line. Morse vs O'Reilly was decided in Morse's favor, but Smith vs Downing went against Morse, and no injuction was granted against the House telegraph. There was extensive expert evidence in especially the latter two cases, all of it in favor of the defense. The evidence presented in Smith vs Downing contains ample proof that Morse's claims were excessive and baseless. Joseph Henry said "I am not aware that Mr Morse has ever made a single original discovery in electricity, magnetism or electro-magnetism applicable to the invention of the telegraph." Every scientific witness said essentially the same thing. Dyar, the inventor of a static electricity telegraph in 1826 said: "The great fault of Morse and his friends hs been, to claim the exclusive use of principles which he never discovered or invented." Prescott lists 62 inventors of telegraphs prior to Morse in 1838. Steinheil was recognized as the inventor of the practical recording telegraph, including the relay, by 1837.
In spite of the evidence, Judge Kane found for the plaintiffs, in a decision that was greeted with incredulity. Either the judge's mind had failed, or there was something else at work. Philadelphia, where the trial was held, was noted for corruption, and something like it may have penetrated here. Bain was Scottish, and that also may have been a factor. On appeal, Judge Cranch found for Bain, but the damage was largely done, and Kane's decision served the public and honest inventors very poorly. It was as if the inventor of the steam engine had patented steam in all its uses and could successfully sue the inventor of a steam hammer. It was said facetiously that the patent commissioner thought that "Mr Morse held exclusive right to electricity in any form in which it could be used for telegraphic purposes," and believed himself put at the head of the Patent Department solely to maintain Morse's rights.
Both Bain and House had quickly received British patents, but the U. S. Patent Office refused them. Both Bain and House appealed to the Supreme Court, which found in their favour, Judge Cranch for Bain, and Judge Woodbury for House. Nevertheless, Morse's patents on the recording and acoustic electromagnetic telegraphs were upheld until they finally lapsed, to the great disadvantage of the public. Curiously, the same competition between Morse, Bain and House (or Hughes; see below) systems existed in Continental Europe. Morse even patented a chemical telegraph, to head off the threat from Bain. Few inventors were ever less entitled to their patent rights than Morse.
The mechanical parts of the telegraph had every right to patent protection, by Vail as part of the Morse Group. These were good, useful inventions of great commercial value. Morse had achieved the federal subsidy by his persistence and devotion, and had seen the enterprise through. It was very unjust, however, to claim exclusive rights to things that others had discovered, and were well-known or had been given to the public by men like Faraday, Henry and Steinheil. The attempt to patent the transmitting key is one example, or the later attempt to patent chemical reception when Morse had been unsuccessful in realizing it earlier. Both things were merely the state of the art, and had already been published and used. In the same vein, Page patented the spring return of an electromagnetic armature! Such a device would have been obvious to anyone, and it is essentially patenting springs. Such greed and presumption, however, are still not rare.
Wheatstone's automatic telegraph (1855) used a punched paper tape to control the transmitter, and could send at speeds up to 130 wpm. Later equipment could send 300 to 400 wpm on a good circuit. The system consisted of a perforator, transmitter and receiver. Holes side by side sent a dot, and staggered holes sent a dash. Polarized pulses were used, two of opposite polarity for each dot or dash, received by a sensitive polarized relay. The receiver was essentially a sensitive Morse register that inked a tape, which was later transcribed in the usual fashion. Wheatstone's automatic transmitter was used on the busy lines of the Electric and International Telegraph Company between London and Manchester, Glasgow, Edinburgh and Newcastle. The Wheatstone was very convenient for sending the news, since only one tape had to be made for transmission of the same news to numerous offices. Edison also worked on automatic telegraphs, and invented a means of sharpening the pulses for higher speed. He achieved 1000 wpm on high-quality pole lines, using electrolytic receivers (like the Bain).
When T. T. Eckert and G. B. Prescott, General Manager and Electrician, respectively, of Western Union visited England in 1874, they brought back with them a pair of Wheatstone instruments as curiosities. When increasing traffic demanded some remedy, the Wheatstone was tried on a New York-Chicago circuit in 1881 and did quite well. The Wheatstone was brought into regular use in 1882 on duplexed circuits to Chicago, New Orleans and Kansas City. There were repeaters at Buffalo on the Chicago circuit, and at Lynchburg and Atlanta on the New Orleans circuit. These were duplex Wheatstone repeaters from England that could handle the necessary speed. 150 wpm was reached on the Chicago line, and about half this on the poorer New Orleans line. Perforating could be done at 30 wpm, and several perforators could feed one transmitter. Received messages were typewritten by female clerks. In 1886, there were 3 Wheatstone instruments and 10 perforators at the New York office, and the company owned 16 Wheatstones in all. This forebode the eventual replacement of manual operation by automatic telegraphs.
In spite of many attempts to design fast automatic telegraphs by many American inventors, notably Edison, only the Wheatstone, from England, ever saw significant practical use. The American Rapid Telegraph Company used some combination of automatic tape transmission and Bain reception with a two-line telegraph (like Steinheil's!) to offer service in 1879. Their secret weapon was the use of young girls as cheap labor. An 1884 lease to Western Union eliminated the competition. Elisha Gray's harmonic telegraph of 1874, Leggo's automatic transmitter, and Snow's compound wire were brought together in the Postal Telegraph Company of 1881 as a "high tech" wonder on the New York-Chicago route. Two compound wires on 43 chestnut or cedar poles per mile, beside the Erie and the Lake Shore and Michigan Southern roads offered 20 words for a quarter. The "postal" in the company name and the cheap rates were to encourage government interest as a possible post office adjunct. Western Union bought it out instead, putting an end to the nonsense. Gray's Harmonic Telegraph led to interest in the multiplex, sending several messages at the same time on one wire, which was finally practically accomplished in another way. The multiplex is explained below in the section on repeaters, duplex and quadruplex.
Cooke and Wheatstone both worked on electrically-released dial telegraphs on which a hand would point to the desired message or character, so that skilled operators (and their wages) would not be required, or that the telegraph could be operated by the general public. Wheatstone realized this principle in his ABC telegraph. After Wheatstone, many inventors came up with alphabetic dial telegraphs, which should be distinguished from alphabetic printing telegraphs. The dial telegraphs were not recording. They were usually called ABC telegraphs, after Wheatstone's instrument. In Wheatstone's instruments, pulses were generated by a hand-turned magneto, and needles on the transmitter and indicator moved synchronously to letter after letter in a message, returning to the zero postion (Maltese cross) at the end. ABC instruments could be used by anyone, and were mainly used on private circuits. All the early visual and printing alphabetic telegraphs did not use a telegraphic alphabet, but relied on synchronism at the two ends of the circuit.
John Nott patented a dial telegraph on 20 January 1846 that was tried on a five-mile circuit between Northampton and Blisworth on the London and North Western Railway. The patent was purchased by the Electric Telegraph Company, but was never used to any extent. One may have been used for a while in Box Tunnel on the Great Western Railway around this time, since the company was their telegraph contractor.
The Hughes printing telegraph, invented by David Hughes, an obscure music teacher of Kentucky around 1855, patented in 1857, but developed in England and used chiefly on the continent, had a type wheel at the receiver synchronized with a wheel at the transmitter by means of tuning forks, with a pulse of current to print the letter at the proper phase, like a ticker. However, the type wheels were synchronized in a different way than in the ticker, and the printing used very little electrical power. It was much easier to use than the House telegraph, but more complex. A skilled mechanic had to be on hand with the Hughes teleprinter, since it was very delicate. By 1870, the House and Hughes teleprinters had been improved and combined by Phelps, whose American Printing Telegraph or Combination Printer helped the American Telegraph Co. and Western Union to dispense with skilled, and unionized, Morse operators on a few lines. The Hughes-Phelps teleprinter was used mainly in Europe, where it became relatively popular, but it was never used to any extent in the United States. It came too late to make any difference in the patent battles. Émile Baudot devised a printing telegraph using the 5-bit Baudot Code in 1874 that was the ancestor of ASCII, but printing telegraphs were really not easy to use until Kleinschmidt's introduction of the Teletype in 1928. These later developments are on the same principle as the Hughes, but with resynchronization for each character.
Stöhrer used a polarized relay to select when one stylus or the other would print dots and dashes on a moving paper tape. The use of four symbols rather than two made the characters more compact, increasing the speed of transmission. The system, an elaboration of the Morse register, was never widely used.
In England, Bright's Bell was an early acoustic telegraph receiver. Two single-stroke bells of different tones were rung by polarized pulses, a positive pulse ringing one and a negative pulse the other, signifying the dots and dashes of the International Code. A modification of this was the Double Plate Sounder, and another was Neale's Acoustic Dial, essentially a needle telegraph that gave acoustic output, so it could be used either visually or aurally.
Major Cardner, R.E. invented what he called a "vibrating sounder" in 1881 shortly after the arrival of the telephone. The receiver was a telephone receiver, but the sender was a vibrating buzzer coupled to the line through a transformer (like an induction coil), operated by a key in the usual way. The power supply was 4 Leclanché cells, so the apparatus was quite portable. At the time, telephones depended on the feeble energy supplied by the voice, and had a very limited range, but Cardner's telegraph was good for up to 300 miles. By using a capacitor and an inductor to separate the signals, the device could be used over a normal Morse wire. A similar device was Edison's phonoplex system used for through traffic over a normal circuit. The way-station relays were bypassed by capacitors, and the audio-frequency signal was separated from the Morse direct current by capacitors.
In 1849-1850, G. H. Horn invented an "igniting" telegraph receiver that used a loop of fine platinum wire to register on a paper tape by burning a brown spot. This receiver was used on a local circuit, so the obviously large current requirement was not a drawback. However, it was a solution for which there was no problem, and soon disappeared. A man named Johnson devised a telegraph in which electricity released certain amounts of lead shot, which was then pressed to make an indentation as a record. "Axial" telegraphs using solenoids were also proposed, by Daniel Davis of Boston, for example.
I believe I have mentioned most of the telegraphs that were used commercially to any extent, or which show the various techniques employed, but there was a very large number of proposals, patents and promotions which forms a study in itself. After about 1880, there was a flood of patents for automatic telegraphs, stock tickers, alarm and call systems, and other electrical inventions, few of which were ever exploited.
In 1844 a government commission was formed in France to investigate the telegraph. The Cooke and Wheatstone needle telegraph was installed between Versailles and Orleans in that year. On 30 January 1845 construction began on the first permanent line, from Rouen to Paris, under the direction of Bréguet and Froment, the leading French telegraph engineers. Louis-François-Clément Bréguet (1804-1883) was of the Huguenot family famous for clocks and instruments, the grandson of Abraham-Louis (1747-1823). A needle swinging between the two poles of a horseshoe electromagnet was the first receiver, but an instrument, based on electrically released clockwork, that simulated the signs of the Chappe optical telegraph was soon devised. Sending was by means of two handles that simulated the controls of the Chappe apparatus. This instrument, however, was used only to send alphabetical and numerical characters, not the Chappe symbols. The long regulator was horizontal, and only the two indicator arms rotated, each taking seven positions. It was essentially two telegraphs in one, and required two wires, in addition to the earth return. The first dispatch was sent from Rouen to Paris on 11 June 1845. The code is shown at the right.
This rather cumbersome system was superseded by the dial telegraph, which became the standard in France and Belgium. Both Bréguet and Froment developed such telegraphs in France, Siemens in Germany, and Lippens in Belgium. The idea is to rotate a pointer around a dial by sending a sequence of pulses, starting from some standard position. Bréguet's transmitter had a rotating handle, Froment's a piano-like keyboard. They were thought usable by untrained staff. Eventually, around 1854, Morse registers, and subsequently the Hughes printing telegraph, superseded the Bréguet instruments. Bréguet instruments were used on Italy's first line, from Pisa to Livorno, in 1847. Brussels-Antwerp followed before 1851, probably with Lippens instruments, and Stockholm-Uppsala in 1853, with instruments unknown to me, but probably Morse.
M. M. von Weber says the Cooke and Wheatstone double-needle instrument and bell were used for a railway block on the heavy gradient between Aachen and Ronheide in 1843. The first postal telegraph line in Germany connected Hamburg and Cuxhaven in 1847, using Morse instruments. Steinheil was sent from Bavaria to inspect and report on this development. Another source says Germany's first telegraph line opened in 1849, between Mainz and Frankfurt. The Morse register was generally adopted in Germany, in fact practically everywhere east of the Rhine, preferred to the Siemens dial telegraph and all other non-recording telegraphs. The Vail Code must have been used initially.
In Austria, a certain Baumgartner had introduced the Bain telegraph and was promoting its use. In 1849, Steinheil was appointed Chief of the Telegraph Department in Vienna, by the new Minister for Trade, von Bruck. He and von Bruck were not impressed by the Bain apparatus, and it was replaced by the Morse. Soon, Steinheil had provided Austria-Hungary with a 1000-mile Morse telegraph system connecting all the provincial capitals. It was a cross centred on Vienna, extending to Prague, Lemberg, Triest and Bavaria, with a fifth line east to Hungary and Croatia. Since the Vail code had not been created with the German language in view, some new characters were desirable. It was also recognized that unless some uniformity was agreed upon, there would be chaos in telegraphing between the many different German-speaking states east of the Rhine. The Deutsch-Oesterreichischen Telegraphenverein was formed in 1850 for this purpose. 
At a conference in Vienna, Austria in October 1851, agreement was reached over the instruments to be used, and the code to be employed. The new code eliminated the spaced letters of the Vail Code, as well as the dashes of different lengths. A second conference in 1854 adopted a new code for numerals, as well as punctuation and operating signals. This conference was attended by T. P. Shaffner, who reports the code adopted there in his book. This code was what later was to become the International Morse Code, achieving its essential form at this early date. We see, then, that the greatest impetus for the change was the adaptation of the Vail Code to the German language, and this was probably done under the supervision of Steinheil. A Russian alphabet for Cyrillic letters was also created at an early date, and is shown on the right.
When Baumgartner became Minister in 1857, Steinheil thought it best to depart from Vienna. In 1851 he had set up the Swiss telegraphs, 300 Swiss leagues long (says the source), with 40 stations and 80 telegraphers. The Morse register was later adapted to the use of ink instead of embossing, and was widely used in Europe, popularized largely by Steinheil, and using the new code. English Morse registers were made by Siemens, and continental ones by Digny of France. The fact that the new code was developed in Germany, on the 'Continent' in English terms, probably caused it to be called Continental Morse Code whenever a distinction was necessary. However, the distinction was not long required, since the Vail code probably vanished completely in Europe at an early date.
A telegraph system consisted of the wire line, the instruments, and the batteries used to supply the electricity. This type of line, bare wire suspended above the earth on insulators, was very well adapted to the purpose, with its low capacitance and inductance offering a bandwidth far in excess of what was required. Ground-return circuits were adequate, halving the cost and resistance of the line over those of a metallic circuit. Telegraphs used batteries as the power source from the beginning. Only small amounts of power are necessary, so that batteries are an economical choice. Until the development of efficient dynamos in the 1870's they were the only choice. Even then, until the arrival of mains power from central power stations after 1900, batteries remained the principal source of power, except in the large stations that could support the expense of a boiler and steam engine.
A chemical source of electricity consists of a spontaneous chemical reaction that involves the transfer of electrons from one species of atom to another, where the electrons are made to travel through the external circuit to accomplish the transfer. Half of the reaction occurs at one electrode, where the electrons are removed from an atom and sent through the wire. Chemically, this is called oxidation. This is the negative electrode, or cathode, as Faraday named it, by convention. The other half of the reaction occurs at the other electrode, where the electrons are received and supplied to the atoms that require them, which is called reduction. This is the positive electrode or anode. Any time the electrons do not pass through the external circuit the reaction takes place without useful effect, and is called local action. The solutions between the electrodes, called the electrolyte, must remain electrically neutral by the movement of charged atoms, or ions. Faraday named the electrodes from the movement of ions from (kata) the cathode, to (ana) the anode, which was true. People just assumed the current continued in the same direction through the external wire, but in fact the electrons are moving in the opposite direction. It makes no difference, as the motions are equivalent because the charges are opposite in sign. The U.S. Army decided current was in the direction of electron flow to simplify things for trainees in the Second World War, but this just adds confusion. In old accounts, the cathode, from which electrons came and which was the negative terminal, was called the positive electrode, and the anode, the positive terminal, was called the negative electrode. This was relative to the electrolyte, and the idea was that current flowed from positive to negative. This nomenclature should be avoided, and is mentioned only in case the reader encounters it.
The reaction that is almost always used is the dissolving (oxidation, in chemical jargon) of zinc from the solid metal to zinc ions in solution, releasing two electrons for each atom. Zinc has a strong tendency to do this, which supplies the power. This reaction, essentially 'burning zinc,' is still used in modern batteries. At the other electrode, the electrons must somehow get into the electrolyte to balance the charge of the zinc ions, and they cannot do this on their own. They can unite with water, however, to form hydrogen gas, leaving the negative part of the water, the OH- in the solution. The electrolyte is made acid, so that water is formed again, and whatever negative ion the acid involves is left in the solution. This was Volta's original battery, or pile, and was the first telegraph battery. Strictly speaking, each individual zinc-copper pair formed a cell, and a number of cells connected in series, zinc to copper, is a battery.
Cruickshanks' trough battery (about 1800), called the pile anglaise in France, consisted of a glazed earthenware trough with slate spacers dividing it into a number of chambers. Alternate copper and zinc plates (typically 112 mm x 87 mm) were held in a wooden top, and connected by wires. The battery was usually filled with sand (to prevent sloshing) saturated with acid water, usually dilute sulphuric acid, or even ammonium chloride solution. This battery supplied about 1 V per cell, but only when fresh. If current was continually drained from it, the plates became covered with bubbles of hydrogen and the internal resistance increased, while the terminal voltage decreased, a process inappropriately called polarization. Therefore, open-circuit telegraphs were the only possibility with this sort of battery. Smee invented a cell where the copper electrode was coated with finely-divided platinum. This caused the evolved hydrogen to form bubbles and detach themselves. However, this was only an imperfect solution.
The Daniell cell was invented at King's College, London by Professor of Chemistry J. F. Daniell in 1836, and was called a constant battery because it did not evolve gas, and therefore did not polarize, supplying a constant current. It furnished the unit of electric potential, the volt (1.079V in modern units), as a column of mercury did the unit of resistance, the ohm. The Daniell cell still used the familiar copper and zinc electrodes. The zinc electrode was put in a cup of unglazed earthenware and bathed in dilute sulphuric acid. The porous cup, which did not allow solutions to mix, but permitted ions to pass through, was Daniell's essential invention. The copper was surrounded by crystals of copper sulphate that maintained a saturated solution. Copper sulphate is sometimes called bluestone, so these batteries were often called bluestone batteries. Instead of releasing hydrogen, the electrons were furnished to the copper ions in the electrolyte, which plated out as copper metal on any nearby surface. The purpose of the cup was to keep the solutions separate while allowing electrical conduction by ion migration. If the solutions mixed, local action ruined the battery. When the cell furnished current, the zinc dissolved to form zinc sulphate solution, and copper from the copper sulphate plated out on the copper electrode. No gases were involved at all, so the cell did not polarize. The cell has a fairly large internal resistance, but this was not a serious defect in view of the small currents required, and actually proved an advantage in many applications. It also protected the cell against damage if shorted. The copper sulphate even kept algae under control. However, the porous cup, intended to keep the solutions separate, was rendered impervious after a time by deposition of copper on it as the cell operated.
The Daniell cell was widely used in France before the Leclanché cell was invented in 1866 by a man of that name who was with the Chemin de Fer de l'Est. This cell consisted of a zinc (negative) electrode in an electrolyte of ammonium chloride solution (sal ammoniac). The positive electrode was a carbon rod, packed with powdered carbon and manganese dioxide in a porous cup (positive). When current flowed, the zinc became zinc chloride, while the ammonium reacted with the manganese dioxide to form manganous oxide, ammonia and water. There was no production of hydrogen, and so no polarization. However, other reactions occur that do produce polarization, lowering the terminal voltage and increasing the internal resistance. These reactions are reversible if the cell stands inactive, so the cell is well-adapted to intermittent use. Its terminal voltage is between 1.6 and 1.4 V, usually taken as 1.5. The ammonia evolved by the cell sometimes attacked iron wires in the vicinity. The Leclanché cell is still in common use as the modern 'dry' cell, with a paste electrolyte and throw-away packaging. These dry cells weaken more rapidly than the wet cell, and have a higher internal resistance, but are very convenient.
The Daniell cell was rendered longer-lasting by a modification introduced by Callaud around the 1860s to eliminate the porous cup, which was just coming into service in 1870. It had been noticed that the copper sulphate solution was denser than the zinc sulphate solution, which floated on top of it if they were both poured into the same container. John Fuller in 1852, and C. F. Varley in 1854, had independently suggested gravity cells. Normally, diffusion would soon mix the two liquids, destroying the cell's efficacy, but if a current was drawn continuously, the natural migration of the ions kept the copper sulphate on the bottom and the zinc sulphate on the top, like oil and water. Callaud's cell (in the form used in the United States) consisted simply of the glass crock, a copper star for the bottom, and a zinc casting hung on the side of the crock. Crystals of copper sulphate were arranged around the copper, and distilled water was carefully poured in until the zinc was covered. Crystals were necessary, since powdered copper sulphate would form a crust and dissolve too slowly. A little acid was carefully poured in the top, and the cell placed under load. Soon you had a reliable cell as long as it remained undisturbed and did not freeze, and you could check its condition by looking at it. A little battery oil poured on the top prevented evaporation. The upper solution was clear, while the lower was a deep blue, and the boundary between them should be distinct. Concentrated zinc sulphate solution could carefully be dipped out and replaced by fresh acid, and more blue crystals could be dropped around the copper, until the zinc was consumed, at which time it was best to renew the cell completely. The supplies were easily stored, and the copper recovered was valuable. This was the familiar gravity cell that gave such good service until replaced by more modern cells in the 20th century. As many cells in series as required to supply the required current were used. Batteries, in general, cannot be paralleled for larger currents. Their physical size determines the current that they can safely supply.
In the United States, the usual telegraph line battery was the Grove cell, invented by (Sir) William Robert Grove in England, which was used on the first Morse telegraph in 1844. This consisted of a glass tumbler, in which a cast zinc cylinder was placed. An unglazed pottery cup was placed in the zinc cylinder. The zinc cylinder had an arm reaching to above the unglazed cup of the neighbouring cell, to which a strip of platinum foil was soldered, that entered the cup. The cup was filled with concentrated nitric acid, and the glass tumbler with dilute sulphuric acid solution. Wires were soldered onto the ends of the battery to make connections. The platinum was the positive terminal, the zinc the negative. When current was drawn, the acid decomposed, releasing noxious fumes, instead of polarizing the cell. The Grove cell had about twice the voltage of zinc-copper batteries, which was its principal advantage. When in use, the cell gave off nitric oxide, N2O4, a poisonous gas. The expensive platinum electrode was replaced by a much cheaper one of carbon in the Bunsen or Carbon cell, where an acidic potassium dichromate electrolyte replaced the nitric acid. Grove also invented a fuel cell using hydrogen and oxygen, but it did not see practical use.
Vail's original Grove cell was in a tumbler 3" high and 2-3/4" in diameter. The zinc was 3" high and 2" in diameter, 3/8" thick, the unglazed cup 3" high under the rim, 1-1/4" in diameter, and 1/8" thick, with a 1/4" rim.
American telegraph circuits were very poor, suffering from high and variable leakage (as well as vandalism). Instead of improving the circuit, one simply piled on more batteries. It was not unusual to use 50 Grove jars on a long circuit. The usual ratio was one Grove cell per 20 miles of relay line (where local circuits had separate batteries). 50 jars could supply an 800-mile relay circuit, or a 50-mile register circuit. Half of the line batteries were placed at one terminus, the other half at the other terminus. With closed-circuit operation, intermediate stations needed only local batteries, usually two or three jars of gravity.
The Grove and Bunsen cells supplied about 2.14 V, and had an internal resistance of about 0.5 Ω for the usual 1-pint cell (3" dia by 4-1/2" high). The Daniell and Gravity cells supplied about 1 V, and had an internal resistance of about 2 Ω for the usual 1-gallon cell (6" dia by 8"-9" high).
Fuller's Patent cell, or Leffert's Patent, had a zinc cathode whose base was immersed in liquid mercury, in a porous container with a dilute sulphuric acid solution. The anode was carbon, surrounded by orange-red potassium dichromate (K2Cr2O7) solution and crystals, again in sulphuric acid. When three zinc atoms lost two electrons each and went into solution, the six electrons passed through the external circuit, and were then supplied to two Cr atoms, changing them from valence 6 to 3 and producing Cr+++ ions. Sulphate ions diffused through the porous pot to complete the circuit. This cell had a terminal voltage of a little more than 2 V, and had the advantage of not producing any noxious gases. However, the dichromate was not cheap.
Impurities in zinc, such as iron or nickel, caused local action, which were minute short-circuited cells around each grain of impurity that would soon eat away the zinc. Pure zinc was far too expensive to be considered at that time, so the commercial metal had to be used. It was found (by William Sturgeon in 1835) that if the zinc electrodes were amalgamated with liquid mercury, the local action was eliminated. To do this, the electrode was first pickled in hydrochloric or sulphuric acid, then dipped in mercury, and then allowed to drain. This isolated the impurities from the electrolyte, while still permitting the passage of zinc ions and electrons, greatly extending the life of the zinc. Amalgamation had to be repeated as necessary. If the zinc is bathed in zinc sulphate solution, as it is in a gravity cell, local action is unimportant, and the zinc need not be amalgamated.
Several varieties of batteries were used in British railway telegraphs of the 1870s, among them the 'sulphate' battery, which was the common American gravity cell, described above. Each 4 miles of line with instruments, or 10 miles of plain line, called for one cell. Tyer's mercurial battery (silver and Hg-covered zinc in dilute sulphuric acid ), Fuller's Patent mercury-bichromate battery, and the wet Leclanché battery were also used. It is remarkable how many batteries used elemental mercury at that time, usually for contacts or for preventing local action at the zinc. Batteries using nitric acid, or poisonous soluble mercury salts, were thankfully becoming infrequent by this time. Despite modern exaggeration of hazards, liquid mercury is relatively harmless, so long as the vapour does not hang around.
All the cells so far mentioned were primary cells, which meant that they produced electricity independently and irreversibly, consuming the materials of which they were made, usually zinc metal. The only other source of current electricity was the magneto, which produced only pulses or an alternating voltage. The magneto was rarely applied to telegraphy, and that mainly in Germany. The storage battery, made of secondary cells, was invented by Planté in 1859, using the reversible chemical change of the oxidation of lead in a dilute sulphuric acid solution. These cells were time-consuming to manufacture, since they had to be "formed" gradually. In 1880, Camille Faure discovered how to manufacture them ready to be charged, by stuffing the plates with ready-made lead peroxide. This was around the time that the first good direct-current dynamos were being designed, and the two worked together quite well. The chemical action in secondary cells is reversible, so they can serve to store electricity, as well as providing a constant-voltage source (each lead-acid cell supplies about 2 V). Later, in large offices telegraphs were operated from storage batteries charged from a small steam engine, or other prime mover, and later from the electricity mains, but this was long after our period. The storage batteries made the electricity supply to the telegraph uninterruptible, as it had been with primary cells.
Storage batteries were specially useful for common-battery operation. Several circuits requiring about the same voltage could be supplied from the same battery. This was satisfactory when the internal resistance of the battery was considerably lower than the parallel equivalent of the resistances of the separate circuits. Since lead-acid cells have very low internal resistances, they were ideal for this application, whereas gravity cells, for example, were not.
In the United States, the Grove cell was used from the beginning until after the Civil War for most telegraph lines, whether open or closed circuit. The Vermont and Boston Bain line, which was naturally open-circuit, used the primitive but cheap sand battery. The bichromate cell began to replace the Grove around the time of the Civil War, saving the batteryman's lungs. After the Civil War, the Callaud gravity cell replaced all other cells for static use. In 1886, Western Union used 12,500 jars of gravity in its New York offices. Every year, they consumed 35,000 lb of copper sulphate, 9000 lb of zinc, 3000 lb of copper (which was recovered) and 8 barrels of battery oil.
Dynamos used in large offices supplied nominally 60 V. If five were available, they could be connected to supply up to 300 V to a circuit, which was the highest voltage used, in steps of 60 V or 70 V. The current supplied to a circuit was adjusted by a rheostat. They had to be driven by a prime mover, a steam engine or perhaps an internal combustion engine of some type, which were becoming available at this time. Storage batteries could also be used, which gave the advantage of an uninterruptible supply, and a fine adjustment of the voltage. They could be charged by a dynamo, or by the local electricity supply, very conveniently if it was the three-wire Edison 220 V direct current available in the centers of large cities. Local circuits were 6 to 7 V.
The telegraph wires of 1845-47 were #14 or #16 BWG (Birmingham wire gauge) unannealed copper. These weak, soft wires stretched and broke with the usual pole spacings of 20-35 to the mile, especially in the winter. For this reason, iron wire of the same conductivity was adopted, which was necessarily larger in diameter, since the resistance of iron is about seven times larger than that of copper. Reid tells that he used #14 iron tinner's wire to make a repair in Philadelphia in 1846 on the Magnetic when no copper wire happened to be available, and a local ironmonger happened to have some. This convinced the Magnetic to change from copper to iron soon afterwards.
Hugh Downing of Philadelphia, who had interests in the first House lines, manufactured stranded iron cord, as it was called, and introduced it on his lines. There were from three to five strands of #14 or #16 iron wire, which would have had a conductivity somewhat less than that of the copper wire then in use. At the time, it was erroneously thought that conductivity depended on perimeter, not cross-sectional area, based on the fluid analogy of electric current. Nobody knew how to make accurate measurements, anyway. These cords, although made of the best Swedish iron, were ungalvanized and rusted rapidly, in spite of attempts to protect them with tar. The stranded construction tended to hold water. The first iron conductor seems to have been used by O'Rielly on the Philadelphia to Baltimore line for the Magnetic Telegraph Company in 1845. It was a four-stranded cord, tarred to prevent rust. Downing used 3 x #16 cord on the New York-Philadelphia line of the New Jersey Magnetic Telegraph Company, the House competitor of the Magnetic. Copper wire could usually be sold for enough to pay for the conversion to iron. When iron cord was broken, it tended to unravel and thrash around wildly and dangerously.
Marshall Lefferts, with interests in Bain telegraphs, imported galvanized solid wire from England, where its use was standard. Lefferts later manufactured this excellent wire himself in New York. H. J. Rogers used galvanized wire on the Baltimore-Harrisburg line in 1847, but it did not appear in any amount until Bains lines were built. Many Morse lines, acquiring the Bain lines that paralleled them, found them far superior to their own, and transferred their traffic to them. The best wire was about 1/6" in diameter, #8 BWG in England, and the thinner #9 in America (wire diameters are smaller as the gauge numbers become larger). Pope says the #9 wire had a resistance of about 16 Ω per mile, and a weight of 320 lb per mile. In 1870, it cost $0.0775 per pound, or $24.80 per mile. In America iron wire, other than this good, heavy wire, was not usually galvanized, as an economy (a false one).
Moses G. Farmer and G. F. Milliken developed the American Compound Wire in 1865-66, which was copper-sheathed steel, with the same conductance as #8 iron wire, but weighing only 80 lb per mile. The copper was apparently applied in the process of drawing. This wire suffered from electrolytic corrosion of the iron in contact with the copper, and was not succesful. C. Snow's compound wire of around 1875 had the copper applied by electrolysis to produce a closer bond. Wire weighing 525 lb per mile, 3/5 copper, was manufactured at Ansonia, Connecticut. In 1883, the National Telegraph Company strung hard-drawn #12 copper wire on its new New York-Chicago line beside the West Shore and the Nickel Plate roads, up to 10,623 miles of it, but Western Union and most other companies stuck with iron. Hard-drawn copper was strong enough, and it slowly replaced iron, but galvanized iron did not disappear until after 1900.
Splices, joints, or joins, as they were called in the early days, were very important. The Western Union splice was preferred in the United States, the Britannia in Britain. The French adopted a somewhat inferior splice, called a torsade, where the wires were simply twisted together in a dual helix. All wire splices had to be soldered; the negect of this precaution was fatal. Some people assumed that galvanized wire did not have to be soldered, but this was a serious error. Oxidation always ruins a nonsoldered splice very rapidly. In the deprecated hook joint, the first attempt of the inexperienced, wires were bent around each other and the ends twisted, forming interlocking loops at the ends of the wires. These were sometimes found in the first American lines of the late 1840's, causing a great deal of grief.
Wire sizes were usually specifed by a gauge number. The Birmingham Wire Gauge (BWG) was originally used, but different manufacturers had different ideas about what it was. It was also called the Stubs Iron Wire Gauge. In Britain, the Standard Wire Gauge (SWG) was eventually adopted to bring some order to the chaos. The Brown and Sharpe (B&S), or American (AWG), wire gauge was adopted in the United States in 1857, with a uniform series of sizes in geometric progression, in place of the arbitrary sizes of the BWG. The gauge numbers are about the same, but by no means equal. The #9 BWG (148 mils) is about a #7 AWG (144 mils). The AWG was used only with American-manufactured wire, of course, British copper remaining in BWG or SWG. Sometimes, the very logical course of specifying wire by the weight per mile was used in Britain. The usual iron wire varied from 800 to 200 pounds per mile for line wire, with 400-pound wire (171 mils) the usual choice. The usual #6 AWG used in the United States was 162 mils in diameter, weighing 359 pounds per mile. The later, and now obsolete, U.S. Standard Gauge was used for steel products, including wire. The Steel Wire Gauge, or Washburn and Moen Gauge, is now used for steel wire.
The differences in the properties of commercially available iron and copper between the 1850s and the present day should be recognized. The copper used today as an electrical conductor is called OFHC (oxygen-free high conductivity) and is available in several hardnesses. Its conductivity (the reciprocal of the resistivity) is 97% of that of pure copper. Pure copper has a resistivity of 1.678 μΩ-cm at room temperature, and is too soft to make a strong wire. Pure iron has a resistivity of 9.61 μΩ-cm, 5.7 times that of pure copper, and is also too soft for general use. At the time, resistivity was measured relative to mercury, which could be purified by distillation. The presence of impurities (such as dissolved oxygen) and alloying metals always raises the resistivity, sometimes sharply. Good commercial copper in 1870 had a conductivity of about 83% that of pure copper, and ordinary tough copper about 70%. Earlier, the copper available was considerably worse. An arsenic impurity greatly reduces its conductivity, and arsenic was a common impurity, sometimes even added to make the copper harder. Sometimes the copper would crystallize, making the wire easy to fracture. Copper is strengthened by work-hardening when it is drawn, and this also decreases its conductivity a little.
Iron wire was drawn wrought iron, made stronger by work-hardening. Wrought iron consisted of rather pure iron, which would have been a good conductor, and slag, which was an insulator. The best iron was supposed to be Swedish charcoal iron, which was very pure. The fibres of iron were aligned and lengthened when the wire was drawn, but the resistivity was higher than that of pure iron. If we use the common figure of 7 for the ratio of the resistivity of iron and copper wires (6.5 is an often-quoted value), the wrought iron wire would have had a conductivity of 57% that of pure iron. From this data, estimates of the resistivity of actual copper and iron in wires at this time would be 2.4 μΩ-cm and 16.8 μΩ-cm, respectively. Pope's figures for #9 BWG wire gi