Back to the page Historical notes in electronics
Are you interested in how telephones were developed, or possibly invented? Read on....
...the following from a textbook over 100 years old....
"The study of sounds produced by electricity remained for a long time in the domain of theory....
"Whatever may be the value of these proposed theories regarding this interesting question of molecular physics, the facts recently brought to light in the invention of the telephone have acquired such an importance, and their applications have made such developments, that all details relating to them are of interest.
"The first sounds that were transmitted to a distance by electricity were merely small tinkling sounds, one of which was heard in the iron bar each time it was magnetised or demagnetised. Wertheim proved that the pitch of the note was the same as that emitted by the bar when struck at the end - proving that magnetisation set up a longitudinal vibration. The first person to discover that electric currents sent out by a proper electrical transmitter could impose upon an iron mass vibrations other than that of the bar itself was Philip Reis. In the telephone invented in 1860 by Reis this principle was applied. His transmitter was to transmit the sounds electrically to the distant receivers, which emitted all such sounds as were thus imposed upon it. The problem of making a transmitter to work his receiver was imperfectly solved by Reis, though he succeeded in transmitting both words and music.
"Sixteen years later Prof. Graham Bell invented the magneto-electric method of transmission and greatly improved the receiving instrument.
"The fundamental ideas of Reis were based on the construction of the human ear. He had set out with the direct intention of transmitting speech electrically, as he states in the opening sentence of his first paper on the subject, communicated in October 1861 to the Physical Society of Frankfurt-on-the-Maine. But he was at first baffled by the difficulty of finding a form of apparatus that could respond to all the various tones that are simultaneously used in speech......At last he saw that the human ear itself solved the problem, and furnished a sort of type of the requisite mechanism. His first experimental transmitter was therefore an "electric ear". It is still (time of writing 1891, ed) preserved in the Patent Museum in Berlin....
"Strange to say, although Reis's telephones were sent all over the world, this brilliant invention passed into almost utter oblivion. Much misconceptions prevailed at one time about the nature of Reis's invention, and attempts were made to stigmatize it as a mere musical toy. Persons were found, in particular lawyers who were paid for what they said, to declare that Reis's apparatus never did and never would transmit speech, and ingenious theories were proposed to prove that it could not...
It was Sellar and Yeatman, in the book "1066 and all that", who said
that history was not necessarily what actually happened, but what
you remember or believe...It is interesting that there are cultural
differences between American and European science. In the USA
one takes a democratic vote on what may happen if one performs
a certain activity, and one goes along with the majority decision.
In this case, it might even be rather easy to reconstruct
Reis's apparatus according to the surviving descriptions
and see how well it does work....There is a modern, and sometimes
pernicious, development of the democratic vote method of conducting
science, in which many of us perforce have to participate. This is
called peer review. In peer review, one is presented with
a paper or patent application and asked for an opinion as to
whether the system described actually works as advertised.
Very rarely, the reviewer goes into the laboratory and tries
to repeat the experiment as described. More often he ventures
an opinion which for one reason or another he feels is acceptable
and defensible to the people asking for the review.
If there is an accepted body of expert opinion that something
does not work, it is very difficult to get the reviewers
to take the proposal seriously enough to try it for themselves.
One wonders, in all the billions of dollars spent by Bell Labs
over the years, whether anyone has tried to make a Reis telephone,
and if they did, whether they were allowed to publish the results.
It is another example of the science and engineering being distorted
by the demands of business.
"In the early instruments that we have described the function of the transmitter was merely to modify or perturb (in correspondence with the vibrations of the wire) a current generated in a battery. If they did not speak as well as the modern instruments do, it was partly because of a want of sensitiveness in the receiving apparatus, partly because of mechanical imperfections which prevented the correspondence between the vibrations of the voice and the fluctuations impressed upon the current from being perfectly observed. Reis himself found that consonants were more perfectly transmitted than vowels by his apparatus, and sought to investigate the phenomenon and to remedy it.
"When in 1876 Graham Bell approached the question, he sought a different solution to the electrical part of the problem, though like Philip Reis he started from the human ear as a model. He proposed to make the vibrations of the voices themselves generate the electric currents by applying the diaphragm of the transmitter to operate a magneto-electric induction apparatus. He thus invented the Magneto-telephone. Ten years have scarcely elapsed since that invention, which the great British physicist, Sir W Thompson, characterised from its commencement as the marvel of marvels; and although we have largely ceased to use Graham Bell's actual method of transmitting, the impetus which his invention gave to the subject of the telephone has spread everywhere; already a score of other applications have arisen for Bell's form of apparatus showing what good fruit an original idea always bears in the field of scientific research." Reference: Electricity and Magnetism, by A Guillemin, published in 1891 by Macmillan, London and New York. Chapter 7 pages 688-693.
Above is the sentence ..we have largely ceased to use Graham Bell's actual method of transmitting....
Here is an extract from the book ENGINEERING by Gordon D Knox, published about 1914 although, curiously, there is no publication date in the book. The publishers were T.C. and E.C Jack, Ltd, London and Edinburgh. The volume is one of a series entitled "The Romance of Reality".
Chapter XVI (16) is entitled "Telephony". We read (page 229)
"The essential of Hughes's discovery is astonishing in its simplicity. Suppose that you have the sounding-box of a violin and you place two ordinary nails on it with a third nail lying across them, making the nails form part of an electric circuit, the effect of the vibrations in the wood is such as to alter the contact between the nails so that the electrical resistance offered by them varies in accordance with the vibrations produced by the voice. An even better result was given by means of small rods of carbon dipping into carbon cups."
This is taken from the ITN "Book of Firsts" by Melvin Harris, published by Michael O'Mara books in 1994, ISBN 1-85479-737-9, pages 107-108. We give only limited excerpts but the original repays a read.
"The first commercially feasible telephone had to wait for Bell.....Bell's first production telephones worked without batteries, since they generated their own power; but this power was unsuited to long distance working... This resulted in the substitution of special carbon microphones as transmitters... Bell's invention survived, but only at the receiving end. The loose contact carbon microphone was David Hughes's great contribution...."
"(Bell's) master patent was filed on 7th March 1876. It has been described as `the most important patent in world history'. Not everyone agrees!..."
This is from a section in "The Children's Encyclopaedia" edited by Arthur Mee, an immediate post WWII edition dating from the late 1940s....
A great step forward was taken in 1860 by Professor Philip Reis, of Friedrichsdorf, who discovered a principle of transmission which was eventually developed into the modern telephone.
Philip Reis was the son of a German master baker and small farmer, and was born at Gelnhausen in 1834. Even when he was a boy of six his teacher recognised that he had remarkable gifts, and at the age of ten he was an enthusiastic reader not only of German, but also of French, English, Latin, and Italian books ; and he was keenly interested in mathematics and science, At sixteen he was obliged to go into business, but continued to attend classes in mathematics and physics and natural history with the intention of becoming a teacher ; and in 1858 he succeeded in getting a teaching appointment at Friedrichsdorf. There he investigated the question of the transmission of sound.
In the course of his researches the idea came to him of using a disc or plate, set into vibration by sound, to make and break an electric current, and of using the current so made and broken to set up similar vibrations in a distant disc, thus reproducing the original sound waves. The idea had been suggested a few years previously by a Frenchman named Charles Bourseul, but it occurred independently to Reis, and he gave it practical shape. He invented the first telephone.
His telephone was of a primitive sort. The bung of a beer barrel was hollowed out, and the cup so made was covered with a diaphragm made of a bit of German sausage skin. To this diaphragm was fixed a little strip of platinum, and as the platinum rose and fell with the vibrating diaphragm it made or broke an electric circuit. The receiver was a knitting needle surrounded with a coil of wire and placed on a violin as a resounding board. The needle and board were set by the interrupted current into vibrations corresponding to the vibrations of the diaphragm, and so gave forth similar sounds.
The bung of a beer barrel, a piece of skin, a magnet, a coil of wire, a knitting needle, and a talking-machine had been made. But, though Reis transmitted music and the human voice over his telephone, it was never able to articulate words, and not till fifteen or sixteen years later was a real talking-machine invented. Then a remarkable thing happened, for two inventors, Alexander Graham Bell and Elisha Gray, invented successful telephones and patented them on the same day.
See also
Reis's original transmitter was a kind of impacting system. One can get a good idea of the sort of sound it would have made by holding a pencil against the cone of a loudspeaker. Such impacting systems are now known to generate chaos in great profusion; however in a chaotic system the periodic driving frequencies often appear above the background noise-like chaos. The combination of tissue paper and comb, used for making "interesting" musical sounds in primary schools, is another example of the application of impacting systems to sound production.
Since consonants are produced in the voice by sibilants and fricatives, generating a characteristic chaotic sound by means of impacting systems, it is not perhaps so surprising that the original Reis telephone was better at communicating consonants than at communicating vowels.
In West Africa, communication at a distance in the 19th century was frequently achieved by means of "talking drums". In contradistinction to the Reis telephone, these were very good at mimicking in nuances of vowel sound in the West African native languages. West African language is rich in vowel sound and light on consonants. The lower frequencies in drum-produced vowel sounds attenuate relatively slowly in jungle. A variable-tension drum is basically a tone generator whose frequency can be moved very quickly; it lacks the harmonic generation and sub-harmonics and chaos of a classical chaotic impact system.