Technical details are sparse in this review, but the inventor apparently planned to use telegraph lines to remotely and simultaneously play various instruments, such as pianos, placed at scattered locations. However, although he had been promoting the idea for over three decades, not even a demonstration system had ever been set up -- nor is it likely that one ever was.
Electrical Review, November 14, 1891, pages 172-173:

Musical  Telegraphy.


    It is a matter of interest to go through an analytical investigation of the first ideas, emotions and circumstances that led the inventor to an important invention. His mental application on the subject of his invention from beginning to end is a process of evolution. His first plan may be crude and even confused, but still it may retain something, the nucleus, that may prove mighty and wonderful in results. No one can fathom this metaphysical question better than the successful inventor himself. But in connection with this question, how many take in the dawn of great ideas that point to great inventions, that cease their prosecution in one or the stages of their progress--sometimes even at the very point of consummation, and, therefore, may run amiss of great renown and even wealth. G. P. Hachenburg
    I would hardly be warranted to open my subject in this style if certain leading electricians of this country had not given me their favorable recognition of my musical telegraphy in a manner that led me to flatter myself that I am the pioneer of an invention that in the near future will assert its importance as one of the great inventions of the age.
    For years in the progress of my study on the subject, I held in high consideration its importance, and became more fully confirmed in this view after taking counsel with wiser and more experienced men than I claim to be myself. Prior to 1860 I presented the subject to the late Professor Henry, and it will ever be with grateful feelings I will think of that great man for the encouragement he gave me in this invention. So sincerely was he interested in it that he offered me the use of the upper floor of the Smithsonian Institute for experimental purposes, and I am fully convinced, if circumstances had been such that I could have accepted his offer, he would have co-operated with me to bring the invention to a practical issue.
    Of late years my correspondence with Bell, Edison, Blake and other noted electricians, gave me a further guarantee as to its practicability. Although receiving this encouragement in casual ways, I have my doubts if the full scope of musical telegraphy was taken in by any of these eminent electricians.
    The main features of my system of musical telegraphy are as follows:
    1. The electrical connection of 10 pianos for concert purposes, to be operated upon by one player, either individually or collectively. This plan we recommend for immediate adoption, and in coming up to our expectations all other plans would be of easy execution.
    2. The electrical connection of 10 organs for church music operated in like manner.
    3. The reproduction of electro-music at a distance.
    4. The electro-musical hall for operatic music, etc., where a great number of musical instruments may be electrically connected, or rather incorporated with the entire inside lining of the building.
    5. Electro-automatic music, by transferring the music from an ordinary music box (properly prepared) to the 10 pianos. The expression of this class of music is governed by a key-board to be described hereafter.
    There are other combinations that could be effected, but the limits of this paper will not allow me to take them into consideration now--as of bells, glass and other metallic contrivances. An electro-bell music could be made very attractive.
    1. To connect electrically 10 pianos, and to operate on them with the best effect, the combination has two key-boards. One that is adjusted to the instrument occupied by the pianist, and has as many keys as there are keys in the piano. By means of this key-board electrical connection is secured with any number of pianos in the circuit. Not to impose new duties on the pianist in playing on these instruments, there is another key-board of 10 keys that is under the supervision of a musical director, who makes and breaks the electrical connection between the 10 pianos for the purpose of regulating the volume and expression of the music. The 10 pianos can be played upon simultaneously, or the most rapid run of notes can be secured without taking two successive notes out of the same instrument. By placing these 10 pianos in a certain position, the notes reaching the tympanum from different points gives the music a timbre that is both grand and peculiar.
    But why limit the number to 10 pianos, or 10 organs, and the small key-board to 10 keys? They are to correspond to the 10 digitals of the musical director. The pianist's manipulations in playing may be exceedingly rapid; such effort is not imposed on the musical director. His 10 fingers cover the 10 keys of his key-board, and by the slightest pressure of one or more of them the necessary connection is made. A more perfect arrangement between the cooperation of the two musicians, I believe, cannot be devised. It will be readily seen that the musical director is the head figure of this order of music, for it is he that (aside of all pedal action) gives it expression relatively with the skill he is able to command. When I explained this feature to Rubenstein, the great pianist, he demurred to the arrangement and asked: "Where is the individuality of such music?" I tried to make him understand that it must be sacrificed, if the music itself can be advanced.
    There may be an impression with some that this combination of pianos is characterized by much noise, like that of an ordinary brass band. Volume is not so much a desideratum as harmony and delicate expression. The ordinary expressions of a single piano are very limited; through the pedals there are but four, and they are very limited through the touch of the player. But, by a mathematical calculation, these 10 pianos have the range of 400 different degrees of expressions for each note. It is simply wonderful how these can be utilized. It is here the mysterious hand of electricity in a new role shows its power to please, where heretofore we only associated it with force and terror.
    It may be rather strange to state that the highest order of music to be effected by these 10 pianos is in accompaniment with the violin, flute or some other musical instrument, or even a brass band, and, in particular, with vocalization. The sympathetic vibration of sounds are well understood by scientists; but where modified by the laws of harmony, under different acoustic effects, as can be enforced by a system of electro-music, the result must be incalculably enhanced.
    2. The main object in resorting to organs for church music is to diffuse the music and to destroy the emanation point where but a single instrument is used. The music would be in harmony with the congregational vocalization. A few concealed organs in the loft would greatly increase the effect. All the organs but one should be of a small size.
    3. There are two methods in reproducing music at a distance--the telephonic and the instrumental--the latter being produced by the direct dynamic operation of electro-magnetism on the instrument in the distance. The former has been tested by several eminent electricians, but never with satisfactory results. The difficulty is in the loss of timbre of several notes in the scale of music. The telephone for the transmission of the human voice has the same defect, in particular with the pitch of some voices. In my experiments I have greatly remedied this defect by placing a small feather cushion between the receiver and the ear. I was led to think that there was a peculiar relation existing between feathers and electricity, believing that there was an "Electro-operation in the Flight of Birds" (vide ELECTRICAL REVIEW, April 28, 1888). The instrumental plan is the only feasible plan to reproduce music in the distance. This may be done by connecting the parent instrument with any number of instruments stationed at different places. One practical utility of such an arrangement, aside of its novelty, is for a distinguished music teacher on the piano to instruct simultaneously many pupils at the same time, living in different parts of a city or even in different towns; and another, having the pianos connected much after the fashion of the telephones, for the exchange of instrumental music between musical friends. Of course, this would demand a central station, as in the telephone, and an "electrical attachment" to each piano.
    4. The most extensive, as well as the most perfect, development of musical telegraphy would be in an "electro-musical hall" containing every variety of musical instruments that could be manipulated by the aid of electricity. The location of these instruments and the acoustic arrangement of the hall would demand the best attention science could bestow. This concord of instruments is not in general, if ever, utilized in unison, but to have on hand to render the greatest variety of music; or, rather, put in action such instruments that are in keeping with the nature of the music to be played. It is here that the musical director, with his small key-board, will prove the wonder of all. Is it possible that a little instrument in the bands of an expert can call forth such a combination of sounds, or almost like a flash cast warbling many thousand notes in the air? Who can tell where these notes come from? The muffled notes from the deep stone vaults underneath, the soft sweet flying notes from above, and a flood of harmonies from all sides, are often blended with extraordinary effects: sometimes falling on the audience much like rumbling thunder and then die away like the sighing zephyr. In this hall there is a stage, such as we see in the theatres; it may be occupied by the managers of the concert or the participants of the opera, a prima donna, or otherwise serve as a relief to the eye. If we are inclined to give the prima donna a pre-eminence with the ten piano arrangement, here she would be placed in an atmosphere of music, where every strain of her own voice would be carried still in deeper melody by this colossal but tender accompaniment. The poet may dream of the heavenly song from the lips of Israfril, but he may soon find her heavenly gifts a terrestrial reality under the mysteries of electricity.
    5. Automatic music has never been popular, and almost invariably has been looked upon with horror by the musicians. There are very good reasons for this from the fact that all appliances producing this kind of music are cheap and miserably constructed. Perhaps the most acceptable of them is the best and most costly kind of the common music box. What merit the best of these instruments have is their action of good time, but their music is deplorably deficient in expression. To make expression in keeping with their time, so mathematically exact, is a matter that can be readily effected by transposing their music under our 10 piano system. The electricians can readily see how a music box can be so reconstructed that it will transfer its music to the 10 pianos, taking the place of a pianist at the large key-board, leaving the task to the musical director to give it expression that would mask every trace of its machine work.
    But there is one feature in this kind of music that is much in its favor. In complex harmony it would supersede that corning from a pianist. For, as the manipulations of the pianist are limited to 10 fingers, such a limitation would not exist by our electro-automatic music. This advantage would have its characteristic effect. It may be hardly necessary to state that the music box itself may be placed out of sight, and beyond the reach of hearing; or it may be of interest to sit close to it and study its tiny accords with the bolder notes from the pianos. Of course, each note from the two would be strictly simultaneously expressed, which, in itself, would be a source of interest. The expression would be nothing like the stiff awkwardness of a duet.
    To prepare a music box for this purpose the cylinder is cut into as many rings as there are notes in the scales; each of these rings is insulated. The steel tongues that produce the notes are insulated in like manner. Without going into details it will be readily seen by electricians how the music is reproduced in the pianos from a music box thus modified.
    I remember in some of my lectures on musical telegraphy I spoke of a "musicometer" in connection with my invention. This instrument was something like a music box, only it was dumb, and the projecting pins in the drum were movable, that is, placed on a slide, and so constructed as to set them to play any piece of music on the 10 pianos. It was nothing else but an electrical test machine of any complex and difficult music; giving very accurately the time in music, but with the expression given by the musical director.
    As to the practicability and commercial importance of musical telegraphy there cannot be the least doubt. The only one that should now be constructed is the first in series. The pianos used in that combination require no reconstruction whatever, except the removal of the pedals. The cost of the different attachments and other incidental expenses would be less than $5,000; but let the entire cost be $10,000, it would prove a very profitable investment, where many hundred thousand dollars could be realized from concerts alone. For who would not pay an admission fee to hear this electro-music? As to the electro-musical hall, a considerable capital would be required to make it a success. But such a hall stationed in any of our large cities would prove yearly the Mecca of many hundred thousand.
    These are some of the outlines of my musical telegraphy I first fixed upon when residing in Springfield, Ohio, several years before the war. But what were the premises on electricity in those days to turn such a scheme into a practical shape. Then our knowledge of electricity was limited, at least so to the writer, although he had experimentally taken some interest in the subject before.
    In 1863, when on a temporary relief from my military service, I wrote out the details of my invention for one of the Cincinnati papers. In the excitement of the war the paper attracted but little attention in this country, but in some foreign land the act was accepted with interest, and its practicability acknowledged by some of the scientists. Godey's Ladies' Book, March number 1864, contains an extract on my musical telegraphy, taken from a London paper that shows that I then based my invention on the telephonic principle, to use a modern expression. I finally came to the conclusion that the telephonic plan would never be of any great service in music. To maintain the purity of musical notes, the plan was changed, by acting on musical instruments direct through electro-magnetic dynamics. On this plan everything now appeared clear, with not a single barrier in the way, to bring it to a ready and successful issue, without resorting to hardly any experimental work. To gain the attention of the public, and the electrical fraternity in particular, I made it the subject of a lecture I delivered in different parts of the United States. This lecture was delivered in the Crosby Opera House, in Chicago, April 9, 1869. It was then proposed, on the part of the audience, to make musical telegraphy a Chicago enterprise, with a view of celebrating the completion of the Pacific Railroad, but it could not be furnished to the Chicagoans in season for their jubilee.
    In 1871, through the courtesy of the Hon. Mr. Lord, of Rochester, N. Y., application was made to the State legislature for a charter to incorporate the Musical Telegraphy Company. At that time I lived in Rochester and took an active part in musical telegraphy rather preparatory to have it introduced at the Centennial celebration. I then proposed to issue stock, after $20,000 stock were ordered. The list was headed, ordering a liberal amount, by the Hon. Charles W. Briggs, Mayor of the city. As the amount was not guaranteed the stock was not issued. I had free access to the three principal dailies of the city, who from time to time accepted my papers on the subject. The nature of these papers was usually explanatory of the subject, and, as in this communication, nothing was kept secret. It was rather remarkably co-incident (as I was told afterwards) that Professor Bell lived in Rochester at the same time and was working on his telephone; and I was likewise informed that Dr. Gray heard my Chicago lecture in 1869.
    In 1872 the subject was presented to the United States Centennial Commission, which met their favorable consideration, as can be seen in their published proceedings for 1872, Appendix 3, p. 92-3. February 19, 1873. I treated the subject in its scientific aspect before the Franklin Institute, of Philadelphia.
    About this time I went to Texas on account of my health, and had to abandon business entirely. Soon after I came here I received an offer from the Shoemaker Piano Co. that they would defray the expenses of constructing the "Electrical Attachments" if I would apply them to pianos of their make at the Centennial. I could not accept their offer, owing to certain conditions.
    In 1890 the manager of the International Electrical Exposition (that was held in St. Louis) asked me to make an exhibition of my invention. He promised material aid to get it ready for the fair. But the time allotted to comply with his request was entirely too short, and I declined to take action in the matter. It will take several months to construct the "Electrical Attachments" on the 10 piano system, and about the same time will be required after they are completed for the musical director to learn to control them with the best effect.
    When it was decided to have a World's Fair in Chicago I offered my musical telegraphy to the Commission on the terms I did to the Commission of the Centennial, asking them to defray the cost of making the electrical attachments for the 10 pianos. They received the offer apparently with interest and asked for many details as to the cost, space, etc. I am doubtful that they will meet my demands, perhaps under the impression that outside capital will bring it into the Exposition anyway. If we are forced to this alternative, let any State, city or electrical association accept the offer I made the Commission and place it in its own department at the Fair. At the same time it will have the faithful co-operation of its inventor to make musical telegraphy a prominent attraction of the World's Fair.