At the end of his fourteenth year, Reis passed to Hassel's Institute, at Frankfurt am Main, where he picked up Latin and Italian. A love of science now began to show itself, and his guardians were recommended to send him to the Polytechnic School of Karlsruhe; but one of them, his uncle, wished him to become a merchant, and on March 1, 1850, Reis was apprenticed as a paints dealer in the establishment of J. F. Beyerbach, of Frankfurt, against his own will. He told his uncle that he would learn the business chosen for him, but would continue his preferred studies as he could.
By diligent service he won the esteem of Beyerbach, and devoted his leisure to self-improvement, taking private lessons in mathematics and physics and attending the lectures of Professor R. Bottger on mechanics at the Trade School. When his apprenticeship ended, Reis attended the Institute of Dr. Poppe, in Frankfurt. As neither history nor geography was taught there, several of the students agreed to instruct each other in these subjects. Reis undertook geography, and believed he had found his true vocation in the art of teaching. He also became a member of the Physical Society of Frankfurt.
In 1855, he completed his year of military service at Kassel, then returned to Frankfurt to qualify as a teacher of mathematics and science by means of private study and public lectures. His intention was to finish his training at the University of Heidelberg, but in the spring of 1858 he visited his old friend and master, Hofrath Garnier, who offered him a post in Garnier's Institute.
On 14 September, 1859, Reis was married, and shortly after he moved to Friedrichsdorf, to begin his new career as a teacher.
Reis imagined electricity could be propagated through space, as light can, without the aid of a material conductor, and he performed some experiments on the subject. The results were described in a paper, "On the Radiation of Electricity," which, in 1859, he posted to Professor Poggendorff; for insertion in the then well-known periodical, Annalen der Physik. The manuscript was declined, to the great disappointment of the sensitive young teacher.
Reis had studied the organs of hearing, and the idea of an apparatus for transmitting sound by means of electricity had been floating in his mind for years. Incited by his lessons on physics, he attacked the problem, and was rewarded with success. In 1860, he constructed the first prototype of a telephone, covering a distance of 100 m. In 1862, he again tried Poggendorff, with an account of his "telephone", as he called it. His second offering was rejected, like the first. The learned professor, it seems, regarded the transmission of speech by electricity as a chimera; Reis bitterly attributed the failure to his being "only a poor schoolmaster."
Reis had difficulty in interesting people in Germany in his invention despite demonstrating it to (among others) Wilhelm von Legat, Inspector of the Royal Prussian Telegraph Corps in 1862. It aroused more interest in the United States In 1872, when Prof Vanderwyde demonstrated it in New York.
Bourseul deserves the credit of being perhaps the first to devise an electric telephone and try to make it; but Reis deserves the honor of first realising the idea as a device to transmit and receive sounds electrically.
Bourseul's idea seems to have attracted little notice at the time, and was soon forgotten. Even the Count du Moncel, who was ever ready to welcome a promising invention, evidently regarded it as a fantastic notion. It is very doubtful Reis had ever heard of it. He was led to conceive a similar apparatus by a study of the mechanism of the human ear, which he knew to contain a membrane vibrating due to sound waves, and communicating its vibrations through the hammer-bone behind it to the auditory nerve. It therefore occurred to him, if he made a diaphragm to imitate this membrane and caused it, by vibrating, to make and break the circuit of an electric current, he would be able through the magnetic power of the interrupted current to reproduce the original sounds at a distance.
In 1837–8 Professor Page, of Massachusetts, had discovered a needle or thin bar of iron, placed in the hollow of a coil or bobbin of insulated wire, would emit an audible 'tick' at each interruption of a current, flowing in the coil, and if these separate ticks followed each other fast enough, by a rapid interruption of the current, they would run together into a continuous hum, to which he gave the name of 'galvanic music.' The pitch of this note would correspond to the rate of interruption of the current. These faint sounds are due to magnetostriction. From these and other discoveries by Noad, Wertheim, Marrian, and others, Reis knew that if the current which had been interrupted by his vibrating diaphragm were conveyed to a distance by a metallic circuit, and there passed through a coil like that of Page, the iron needle would emit a note like that which had caused the oscillation of the transmitting diaphragm. Acting on this knowledge, he constructed his rudimentary telephone. This prototype is now in the museum of the Reichs Post-Amt, Berlin.
The discovery of the microphone by Professor Hughes has demonstrated the reason of this failure. Reis' transmitter was based on interrupting the current, and the spring was intended to close the contact after it had been opened by the shock of a vibration. So long as the sound was a musical tone it proved efficient, for a musical tone is a regular succession of vibrations.The vibrations of speech are irregular and complicated, and in order to transmit them the current has to be varied in strength without being altogether broken. The waves excited in the air by the voice should merely produce corresponding waves in the current. In short, the current ought to undulate in sympathy with the oscillations of the air. The Reis phone was poor at transmitting articulated speech, but conveyed the pitch of the sound.
It appears from the report of Herr von Legat, inspector of the Royal Prussian Telegraphs, published in 1862, Reis was quite aware of this principle, but his instrument was not well adapted to apply it. No doubt the platinum contacts he employed in the transmitter behaved to some extent as a crude metal microphone, and hence a few words, especially familiar or expected ones, could be transmitted and distinguished at the other end of the line. If Reis' phone was adjusted so the contact points made a "loose metallic contact" they would be functioning much like the later telepone invented by Berliner or the microphone of Hughes, one form of which had iron nails in loose contact. Thus the Reis phone worked best for speech when it was slightly out of adjustment.
A history of the telephone from 1910 says, "In the course of the Dolbear lawsuit, a Reis machine was brought into court, and created much amusement. It was able to squeak, but not to speak. Experts and professors wrestled with it in vain. It refused to transmit one intelligible sentence. ‘It can speak, but it won't,’ explained one of Dolbear's lawyers. It is now generally known that while a Reis machine, when clogged and out of order, would transmit a word or two in an imperfect way, it was built on wrong lines. It was no more a telephone than a wagon is a sleigh, even though it is possible to chain the wheels and make them slide for a foot or two. Said Judge Lowell, in rendering his famous decision: 'A century of Reis would never have produced a speaking telephone by mere improvement of construction. It was left for Bell to discover that the failure was due not to workmanship but to the principle which was adopted as the basis of what had to be done. …Bell discovered a new art — that of transmitting speech by electricity, and his claim is not as broad as his invention. …To follow Reis is to fail; but to follow Bell is to succeed."
Reis does not seem to have realised the importance of not entirely breaking the circuit of the current; at all events, his metal spring is not in practice an effective provision against this, for it allows the metal contacts to jolt too far apart, and thus interrupt the current.
His experiments were made in a little workshop behind his home at Friedrichsdorff; and wires were run from it to an upper chamber. Another line was erected between the physical cabinet at Garnier's Institute across the playground to one of the classrooms, and there was a tradition in the school that the boys were afraid of creating an uproar in the room for fear that Philipp Reis would hear them with his "telephon".
Reis obtained a brief renown, but the reaction soon set in. The Physical Society of Frankfurt turned its back on the apparatus which had given it lustre. Reis resigned in 1867, but the Free German Institute of Frankfurt, which elected him an honorary member, also slighted the instrument as a mere "philosophical toy".
Reis believed in his invention, even if no one else did; and had he been encouraged by his fellows from the beginning, he might have brought it into a practical shape. He was already stricken with tuberculosis, however. It is related that, after his lecture on the telephone at Gießen, in 1854, Poggendorff, who was present, invited him to send a description of his instrument to the Annalen. Reis answered, "Ich danke Ihnen sehr, Herr Professor, aber es ist zu spät. Jetzt will ICH ihn nicht schicken. Mein Apparat wird ohne Beschreibung in den Annalen bekannt werden" ("Thank you very much, Professor, but it is too late. Now I do not want to send it. My apparatus will become known without any description in the Annalen.)
Later, Reis confined his teaching and study to matters of science; but his bad health become a serious impediment. For several years it was only by the exercise of a strong will that he was able to carry on his duties. His voice began to fail as the disease gained upon his lungs, and in the summer of 1873 he was obliged to forsake tuition during several weeks. The autumn vacation strengthened his hopes of recovery, and he resumed his teaching, but this was the last flicker of the expiring flame. It was announced that he would show his new gravity-machine at a meeting of the Deutscher Naturforscher of Wiesbaden in September, but he was too ill to appear. In December he lay down, and, after a long and painful illness, breathed his last at five o'clock in the afternoon of January 14, 1874.
In his Curriculum Vitae he wrote: As I look back upon my life I call indeed say with the Holy Scriptures that it has been "labour and sorrow." But I have also to thank the Lord that He has given me His blessing in my calling and in my family, and has bestowed more good upon me than I have known how to ask of Him. The Lord has helped hitherto; He will help yet further.
Philipp Reis was buried in the cemetery of Friedrichsdorff, and in 1878, after the introduction of the speaking telephone, the members of the Physical Society of Frankfort erected an obelisk of red sandstone bearing a medallion portrait over his grave.
Documents in the London Science Museum show, that, in 1947, engineers from the British firm Standard Telephones and Cables (STC) found Reis's device dating from 1863 could transmit and "reproduce speech of good quality but of low efficiency".
Sir Frank Gill, then chairman of STC, ordered the tests be kept secret, as STC was negotiating with AT&T, which had evolved from the Bell Company of Alexander Graham Bell. Bell was generally accepted to have invented the telephone, and Gill thought that evidence to the contrary might disrupt the negotiations.
Besides Reis and Bell, others claimed to have invented the telephone. The result was one of the United States' longest running patent interference cases, involving Bell, Edison, Elisha Gray, Berliner, A E Dolbear, J W McDonagh, G B Richmond, W LW Voeker, J H Irwin, and Francis Blake Jr. The case started in 1878 and was not finalised until February 27, 1901.