Lives of the electricians

by William T. Jeans

In all the inventions and discoveries previously described as made by Professor Wheatstone, his originality has never been seriously challenged, but when we turn to his greatest work we enter upon contested ground. The contests that ever arise as to the origin of great inventions afford evidence of their greatness; for, as Aeschylus says, he who is not envied is not worthy of admiration.

“In 1435,” says Sir James Mackintosh, “a law suit was carried on at Strasburg between one John Guttenberg, a gentleman of Mentz, celebrated for mechanical ingenuity, and Drizehn, a burgher of the city, who was his partner in a copying press. No litigation could seem more base and mechanical to the barbarous Barons of Suabia and Alsace; but the copying machine was the printing press which has changed the condition of mankind.” In like manner it fell to the lot of Professor Wheatstone when he had completed his most useful invention to have his originality disputed by his own partner in business, Mr. William Fothergill Cooke. There are five mechanical inventions that have conferred incalculable benefit on the industrial world in modern times—the printing press, the steam engine, the electric telegraph, the dynamo, and the Bessemer process of steel making. The originality of every one of these has been either divided or disputed, with the single exception of the Bessemer process, which is therefore the only one that is universally known by the inventor’s name. In the case of the electric telegraph the originality or priority of Professor Wheatstone was disputed not only at home but abroad. Hence writers on the subject are accustomed to say that the telegraph was invented independently and almost simultaneously by Professor Wheatstone, of London, Professor Morse, of New York, and Professor Steinheil, of Munich. This was in the year 1837.

After the discovery of the voltaic pile, Oersted discovered in 1819 that if a needle were placed parallel to a conducting wire, an electric current from a voltaic battery applied to the wire would cause the deflection of the needle to a position at right angles to the wire or across the direction of the current. Ampère proposed to make an electric telegraph by utilising this property of a compass needle, and he designed an apparatus to which twenty-five wires were attached; and by touching keys which corresponded to the letters of the alphabet, needles attached to the other ends of the wires were set in motion by the action of an electric current. It was this incipient and very imperfect design that Professor Wheatstone brought to perfection by a series of inventions and discoveries extending over a number of years. His own account of the origin of his telegraph is candid and interesting. “When, in 1823,” he says, “I made my important discovery that sounds of all kinds might be transmitted perfectly and powerfully through solid wires and reproduced in distant places, I thought I had the most efficient and economical means of establishing telegraphic (or rather telephonic) communication between two remote points that could be thought of. My ideas respecting establishing a communication of this kind between London and Edinburgh you will find in the Journal of the Royal Institution for 1828. Experiments on a larger scale, however, showed me that the velocity of sound was not sufficient to overcome the resistance and enable it to be transmitted efficiently through long lengths of wire. I then turned my attention to the employment of electricity as the communicating agent; the experiments of Ronalds and others failed to produce any impression on the scientific world; this want of confidence resulted from the imperfect knowledge then possessed of the velocity and other properties of electricity; some philosophers made out a few miles per second; others considered it to be infinite; if the former were true, there would not be much room for hope; but if the velocity could be proved to be very great there would be encouragement to proceed. I undertook the inquiry, and with the result the whole scientific world is acquainted. At the same time I ascertained that magnetic needles might be deflected, water decomposed, induction sparks produced, &c., through greater lengths of wire than had yet been experimented upon. In the following year, at the request of the Royal Society, I repeated these experiments with several miles of insulated wire, and the results were witnessed by the most eminent philosophers of Europe and America. I ascertained experimentally (which had never been done before) many of the conditions necessary for the production of the various magnetic, mechanical, and chemical effects in very long circuits; and I devised a variety of instruments by which telegraphic communication should be realised on these principles.

“Some time before Mr. Cooke introduced himself to me I considered my experiments to be sufficiently matured to enable me to undertake some important practical results. I informed Mr. Fox, the engineer of the London and Birmingham Railway, of my expectations, and told him of my willingness to superintend the establishment of an electric telegraph on that railway. I had also made arrangements for trying an experiment across the Thames. Mr. Enderby kindly undertook to prepare the insulating rope containing the wires and to obtain permission from Mr. Walker to carry the other termination to his shot tower. After many experiments had been made with the rope, and the permission granted, I relinquished the experiment, because after my connection with Mr. Cooke it was necessary to divert the funds I had destined for this purpose to other uses. What I have stated above is sufficient to show that I had paid great attention to the subject of telegraphic communication by means of electricity, and had made important practical advances long before I had any acquaintance with or ever heard of Mr. Cooke.”

On reading this account two questions arise: first, whether the Wheatstone telegraph was the first of its kind; and, secondly, whether there is any corroborative evidence of the early labours of its inventor. These two questions at the time became interlinked in a singular way. In 1833 the celebrated scientists, Gauss and Weber, placed a line of wire from the Observatory of Göttingen University to a building a mile distant, and by sending magneto-electric currents through that wire they communicated intelligible signals; but as the needle they used weighed nearly a hundredweight they saw that their apparatus needed much improvement before it would be of practical utility. Being otherwise engaged themselves, they invited Professor Steinheil, of Munich, to construct an improved electric telegraph; and Steinheil, after much labour, succeeded in producing an apparatus capable of transmitting signals, but it was too refined for practical working with the means then available. His instrument for receiving and recording the signals consisted of two needles, one of which was to be moved by a positive and the other by a negative current, both currents being sent through one wire. Connected with each needle was a small reservoir of ink and a pen, which, on being depressed by the motion of the needle, marked a line upon a strip of paper that was drawn along by means of clockwork. At first he used a second wire for the return circuit, but in the course of his experiments he discovered that the earth was the best receiver of the return current, and accordingly dispensed with the second wire. Now, strange to say, the experiments connected with this telegraph of Steinheil’s became indirectly a circumstantial witness of Professor Wheatstone’s labours before ever he saw Mr. Cooke.

The number of the Magazine of Popular Science published on March 1st, 1837, contained “an account of some new experiments in electro-magnetism.” It was a description of the experiments of Gauss at Göttingen, communicated to the Munich Academy of Sciences by Prof. Steinheil, who, in concluding, stated that he himself “had fitted up a telegraph similar in principle to that which connected the Observatory and the Cabinet of Natural Philosophy at Göttingen. Signals made in the room appropriated to the magnetic observations were transmitted to another department at a considerable distance, whence the answers were returned to the first room. He had arranged this apparatus for the purpose of demonstrating the peculiarities and the practicability of Professor Gauss’s contrivance, hoping by these means to draw attention to it, and to induce persons to employ it for connecting stations far more distant than any to which it has yet been applied.” To that was added the following: “Note by Editor: During the month of June last year (1836), in a course of lectures delivered at King’s College, London, Professor Wheatstone repeated his experiments on the velocity of electricity, which were published in the Philosophical Transactions for 1834, but with an insulated circuit of copper wire, the length of which was now increased to nearly four miles; the thickness of the wire was 1/16th of an inch. When machine electricity was employed, an electrometer placed on any point of the circuit diverged, and wherever the continuity of the circuit was broken, very bright sparks were visible. With a voltaic, or with a magneto-electric machine, water was decomposed, the needle of a galvanometer deflected, &c., in the middle of the circuit. But, which has a more direct reference to the subject of our esteemed correspondent’s communication from Munich, Professor Wheatstone gave a sketch of the means by which he proposes to convert his apparatus into an electric telegraph, which, by the aid of a few finger-stops, will instantaneously and distinctly convey communications between the most distant points. These experiments are, we understand, still in progress, and the apparatus, as it is at present constructed, is capable of conveying thirty simple signals, which, combined in various manners, will be fully sufficient for the purposes of telegraphic communication.”

These words must have been in type, and most probably were printed before the day on which Mr. Cooke said he first saw Professor Wheatstone; and they were certainly printed before the date fixed by Professor Wheatstone as the time of Mr. Cooke’s introduction to him. Professor Wheatstone says:

“I believe it was on the first day of March, 1837, that Mr. Cooke introduced himself to me. He told me that he had applied to Dr. Faraday and Dr. Roget for some information relative to the subject on which he was engaged, and that they had referred him to me. He gave me no clue as to the purpose he had in hand. I replied that he was welcome to all the information I could give him, and that the experiments I had been making for some time relative to employing electric currents for the purpose of telegraphic communication would enable me to give him much of the information he required. At our next interview shortly after, he told me he was working at an electric telegraph, and that the questions he had previously put to me related to this subject. After that I showed him some of my apparatus, and explained my proposals. Mr. Cooke showed me some of his drawings and models. I at once told him it could not act as a telegraph, and to convince him of the truth of this assertion I invited him to King’s College to see the repetition of my experiments. He came, and after seeing a variety of voltaic magnets, which even with powerful batteries exhibited only slight adhesive attraction, he expressed his disappointment in these words which I well remember: ‘Here is two years’ labour wasted.’

“With regard to Mr. Cooke’s invention, so far from its being practically useful, he has never, during my whole acquaintance with him, shown it to me in action, even in a short circuit. Mr. Cooke’s intention was, as he told me in the early stage of our acquaintance, to take out a patent for his invention. Mine was, when I had finished my experiments, to publish the results, and then to allow any person to carry them into effect. When Mr. Cooke found that his instrument was inapplicable to the purpose proposed, and that my researches were more likely to be practically useful, he proposed a partnership, and that we should take out a joint patent. The proposal did not proceed from me, and the sole reason of my acquiescing in the arrangement was that Mr. Cooke appeared to me to possess the zeal, ability, and perseverance necessary to make the thing successful as a commercial enterprise. I felt confident of overcoming myself all the scientific and mechanical difficulties of the subject, but neither my occupations nor my inclination qualified me for the part Mr. Cooke promised to perform. He said he was not wanting a scientific reputation, his sole object being to make money by it.

“The magnetic needle telegraph, as it appears in its most perfect state in the lecture room of the college, is to all intents and purposes entirely and exclusively my own invention. The original suggestion of Ampère (that a telegraph should be constructed by utilising the tendency of the magnetic needle always to place itself at right angles to an adjoining wire through which an electric current passed) was all that I borrowed in it. The most important point was my application of the theory of Ohm to telegraphic circuits, which enabled me to ascertain the best proportions between the length, thickness, and circumference of the multiplying coils and the other resistances in the circuit, and to determine the number and size of the elements of a battery to produce the maximum effect. With this law and its applications none of the persons who had before occupied themselves with experiments relating to electric telegraphs, had been acquainted.”