Ernest Horkheimer, Esq.
“Manchester, Dec. 2, 1882.
“Professor S. P. Thompson,
“Dear Sir,
“In reply to your favour of 31st instant, I shall be very happy to give you all the information I can with respect to the telephonic experiments of my late friend and teacher Mr. Philipp Reis. I would express my gratification at finding that you are trying to put my old teacher’s claims on their just basis. I have always felt that in this race for telephonic fame, his claims have been very coolly put aside or ignored. That he did invent the Telephone there is not the remotest doubt. I was, I think, a great favourite of his; and at the time his assumption was that I was destined for a scientific career, either as a physicist or a chemist; and I believe that he said more to me about the telephone than to any one; and I assisted him in most of his experiments prior to the spring of 1862.
“Philipp Reis intended to transmit speech by his telephone—this was his chief aim; the transmitting of musical tones being only an after-thought, worked out for the convenience of public exhibition (which took place at the Physical Society at Frankfort-on-the-Main). I myself spent considerable time with him in transmitting words through the instruments. We never (in my time) got the length of transmitting complete sentences successfully, but certain words, such as ‘Wer da?’ ‘gewiss,’ ‘warm,’ ‘kalt,’ were undoubtedly transmitted without previous arrangement. I believe Reis made similar experiments with his brother-in-law.
Fig. 35.
Fig. 36.
“I recollect the instrument in the shape of the human ear very well: it was Reis’s earliest form of transmitter. The transmitter underwent a great many changes, even during my time. The form you sketch ([Fig. 9], p. 20) was almost the oldest one, and was soon superseded by the funnel-shape ([Fig. 35]). The back was always closed by a tympanum of bladder, and many a hundred bladders were stretched, torn, and discarded during his experiments. I recollect him stating to me that he thought a very thin metal tympanum would eventually become the proper thing, and one was actually tried, coated over on one side with shellac, and on the other likewise, except at the point of contact ([Fig. 36]). I believe it was made of very thin brass, but at the time the experiments were not satisfactory. Talc was also tried, but without success, the platinum contacts being in all cases preserved.
“I remember very well indeed the receiver with a steel wire, surrounded by silk-covered copper wire. The first one was placed on an empty cigar-box, arranged thus:—
Fig. 37.
“The wire was a knitting-needle and the copper wire was spooled on a paper case.
“The spiral was supported by a little block of wood, so as to allow the knitting-needle not to touch it anywhere. Later on a smaller cigar-box was invented as a cover—thus; ([Fig. 38])—having two holes cut into it like the f-holes in a violin.
Fig. 38.
“The practice was to place the ear close to the receiver, more particularly so when the transmission of words was attempted.
“The spiral was, during the early experiments, placed on a violin—in fact, a violin which I now possess was sometimes used, as it was of a peculiar shape, which Reis thought would help the power of tone.
“I have already enumerated some of the words which were transmitted, but there were many more; on one occasion a song, known in this country as ‘The Young Recruit’ (Wer will unter die Soldaten) was transmitted, the air and many of the words being clearly intelligible.
“I do not recollect seeing the receiver shewn in the woodcut ([Fig. 21]), but Reis often said that he would make such a one, although the sketch he made for me then differed in some details from your woodcut. Reis intended to keep me fully informed of all he could achieve, but, immediately after leaving his tuition, I fell ill, and was laid up for a very long time. Shortly afterwards I left for England, and then he died, and I never saw him again. The electromagnet form was certainly strongly in his mind at the time we parted, and he drew many alternative suggestions on paper, which have probably been destroyed; but the electromagnets in all of them were placed upright, sometimes attached to the top of a hollow box, and sometimes to the bottom of a box arranged thus (Figs. [39], [40]); but, to my recollection, they never got beyond the stage of drawings, whatever he may have done after he and I parted company.
Fig. 39.
Fig. 40.
“In conclusion, I beg to send you herewith a photograph of Philipp Reis (see [Fig. 12], p. 23), holding in his hand the instrument I helped him to make, and which photograph he took of himself, exposing the camera by a pneumatic arrangement of his own, and which formed part of a little machine which he concocted for turning over the leaves of music-books.
“The instrument used by Reis at the Physical Society may have been the square block form: I believe that this cone-form was not quite completed then. At the Saalbau (Hochstift), however, I am sure the instrument shown in my photograph was employed; not with a tin cone, but a wooden one. I send you herewith a sketch of what I remember that instrument to have been. I am not absolutely certain whether in the instrument there was not an electromagnet introduced, but I think not. My recollection leads me to suppose that the electromagnet arrangement was added subsequently. Thinking it over again, I should, however, think that the instrument in the photo must have been one in which a bent lever was placed behind the tympanum, and that the rectangular patch seen above was a wooden casing to shelter the parts. There may be some confusion in my mind as to the position of this box, but I somehow think the rectangular patch is only part of a larger box which is not apparent in the photograph. I have no idea where the original instrument is now, but I should hardly think it could be in existence. Reis used to take some instruments to pieces to utilise parts in subsequent experiments, and I recollect how keen he used to be about the bits of platinum, which he always described as ‘ein sehr kostbares Metall.’ What always was a great puzzle was the attaching of the platinum plate to the membrane, which he did generally by sealing-wax, saying at the same time: ‘Es ist nicht recht so, aber ich weiss nicht wie es anders gemacht werden kann!’
“Believe me, my dear Sir, yours truly,
“Ernest Horkheimer.”