Heinrich Hold.
[Herr Hold, formerly a colleague of Philipp Reis in the Garnier Institute at Friedrichsdorf, but now proprietor of a leather factory in the same place, was teacher of mathematics. He was in his younger days a fellow-student of Professor Tyndall at Halle, and was well acquainted with physical science in general. His intimate connection with Reis, and close knowledge of Reis’s work, enable him to confirm the testimony of others in many important points.]
To Professor S. P. Thompson in Bristol.
“Esteemed Sir,
“I have much pleasure in furnishing you with the following particulars concerning my late colleague Philipp Reis, the inventor of the Telephone. He was himself educated at the Garnier’s Institute in Friedrichsdorf where I was also teacher of mathematics. I knew him very well during his life-time. Among his numerous original researches, his invention of the telephone was the principal one. His idea was to reproduce the tones both of musical instruments and of the human voice by means of electricity, using a covered wire wound in a spiral round an iron core, the same being placed upon a resonant box. In this he succeeded, inasmuch as with an apparatus, which he showed to the Physikalischer Verein in Frankfurt-a.-M., in the year 1861, he reproduced music, singing, single words and short sentences; all of which were distinctly audible over a short distance from his dwelling-house through the yard to the barn. Every voice was not equally well adapted for speaking into the apparatus, neither could every ear understand the telephone language equally well. Words spoken slowly, and singing, both in a middle tone, were the most easy to reproduce. I helped Mr. Reis to make many of his experiments, and have spoken and sung into the telephone, the same being generally heard and understood. I have also heard and understood short sentences when I was standing at the end station. A brother-in-law of Mr. Reis, who is now paymaster in the Imperial Navy at Wilhelmshavn, generally conducted the speaking and singing in the telephone.
“Heinrich Hold.”