June 1, 1897.] 



KNOWLEDGE 



135 



sensibly diminished by the passage of the current through 

 a long conductor — paved the way for the introduction of 

 the electric telegraph, which, however, is a product of the 

 Victorian era. 



Baron Schilling, about 1838, used the deflections of 

 needles to right and left as a means of signalling ; but 

 Gauss and Webber seem to have introduced the use of a 

 single needle, their apparatus being exhibited before the 

 Society of Arts in Edinburgh in the November of the year 

 in which the Qaeen ascended the throne. 



The English electric telegraph is in a great measure due 

 to William Fothergill Cooke. In the latter part of 1836 

 Cooke had the satisfaction of witnessing a trial of his key 

 and needle telegraph on the Liverpool and Manchester 

 Railway. In 1837, with Prof. Wheatstone, of King's 

 College. London, he set to work to perfect his apparatus 

 and to make it less complicated : the result being that in 

 June of 1837 (about the time of the Queen's accession) 

 a practical form of electric telegraphy was patented in 

 England. 



In 1840 Prof. Wheatstone showed, before a Committee 

 of the House of Commons, his apparatus for proposed 

 telegraphing between Dover and Calais. 



In 1812 Prof. Morse laid his wire in New York Harbour 

 for the purposes of electric telegraphing ; and in 184.3 

 Cornell laid twelve mUes of cable in the Hudson River. 



The first concession for international submarine tele- 

 graphy was granted to Jacob and John Watkins Brett in 

 1817. The successful development of submarine telegraphy 

 under the lead of Englishmen like the late Sir Charles 

 Bright need not be further referred to ; but we may note, 

 in conclusion, that there are now more than thirteen 

 hundred submarine telegraph cables in existence, the total 

 length of which is probably not less than one hundred and 

 sixty thousand miles, the cables varying from a quarter of 

 a mile to two thousand six hitndred nautical miles in 

 length. It is notable, however, that whilst there are two 

 hundred and twenty-three cables of between five and fifty 

 miles in length, one hundred and fifty-five are from one 

 hundred to five hundred miles long, and there are only i 

 eight the length of which exceeds two thousand miles. | 



The telephone is, comparatively, in its infancy, yet its ' 

 progress so far has been much more rapid than that of its 

 sister the electric telegraph. Doubtless, its being and 

 wonderful capabilities are due to the researches of Wheat- 

 stone (1821. etc.). Page (1837). Bourseul (1854), and 

 especially Reis (1868). The speaking telephone was, how- 

 ever, only patented (in the United States) by Graham Bell 

 (a Scotchman, naturalized as an American citizen) on 

 February 14th, 1876. EHsha Gray, an American, applied 

 on the very same day as Bell for a patent for a similar 

 apparatus. A compromise was efl'ected between the rival 

 claimants, and to Graham Bell is usually given the credit 

 of the invention. 



Mr. Preece, at the meeting of the British Association, 

 held at Plymouth, in 1877. exhibited, for the first time 

 publicly in England, Bell's telephone. The carbon trans- 

 mitter is due to Edison, and Hughes' discovery of the 

 microphone, in 1878, has done probably as much towards 

 the perftction of the telephone as Bell did towards initiating 

 it. These two triumphs of the latter part of the Victorian 

 age, the telegraph and the telephone, have done more for 

 the advancement of business, and even the spread of infor- 

 mation and the reign of peace, than any other two dis- 

 coveries which the remarkably fertile years of Her Majesty's 

 reign have produced. 



It is a remarkable fact that the two countries which are 

 now competing most keenly with us in the industrial race 

 — especially in those departments aUied to engineering — 



are Germany and the United States ; two which have for 

 many years been in the van in the matter of providing 

 facilities for education in matters pertaining to the indus- 

 trial arts. 



In the matter of technical education we are behind 

 Germany now, and it is doubtful whether, on present lines, 

 we will greatly better our position in the future ; and whilst 

 we rejoice in the phenomenal progress of the last sixty 

 years, our self-congratulation is tempered by some mis- 

 givings as to the future. 



CAN THE DEAF APPRECIATE MUSIC? 



By Dr. J. G. McPherson, F.R.S.E., 

 Late Mathematical Examiyter in the I'niversitt/ of St. Andrew's, 



PROFESSOR McKENDRlCK, of Glasgow University, 

 has laid before the Royal Society of Edinburgh the 

 results of some experiments which indicate that 

 the deaf can be made to understand some of the 

 elements of music. They have been deprived of 

 the ordinary sense of hearing, yet their senses of sight, smell, 

 and touch are intensified. They can understand to some 

 extent what a friend says by observing the motion of the 

 lips. But, according to Prof. McKendrick, the deaf may 

 yet have the means to appreciate music. 



The Professor showed us, a year ago, in the Royal Society 

 of Edinburgh, a beautiful experiment, which originated 

 his new discovery. He suspended a microphone transmitter 

 over a phonograph when the latter was in motion and 

 giving out tones, and showed that the variations in resis- 

 tance in the former produce such attractions in the current 

 flowing through it to the coils of an electro-magnet as to 

 mechanically record these variations. Continuing these 

 experiments, he introduced the microphone- transmitter 

 into the circuit of the primary coil of the induction machine 

 along with four Obach's cells (Q type). He carried the 

 terminals of the secondary coil to two strips of platinum 

 foil, immersed in two shallow vulcanite troughs, containing 

 a -75 per cent, solution of common salt or sulphuric acid 

 (1 : 10 of water). He was then astonished to find that 

 when the phonograph was in motion and emitting notes 

 of music, an electric thrill was felt in his fingers which 

 corresponded to the rhythm, time, and intensity of the 

 tune given out by the phonograph. By carefully graduating 

 the strength of the induction shocks, he distinctly felt each 

 successive note and each chord of the music. This dis- 

 covery at once suggested to him that these whose fingers 

 are exceptionally sensitive because of the defect in one of 

 the senses would appreciate more keenly the meaning of 

 the thrills from the insulated trough, as strange music of 

 a kind. The sensory nerves of the skin can appreciate all 

 the variations in resistance in the microphone transmitter 

 suspended over the phonograph, discoursing familiar tunes.. 

 The only difficulty is the regulating of the strength of the 

 stimulation. If it is too strong, muscular twitchings are 

 excited, and the rhythm of the music is blurred ; but when 

 regulated, the "thrill" is carried to the brain with a 

 correct impression of the sound. 



Now, what structures in the skin are stimulated by such 

 thrills from the electric connection ? To the skin are 

 referred at least two well-defined sensations — touch and 

 temperature. Touch is a sense of pressure, and is con- 

 nected with various kinds of touch corpuscles ; but no 

 end organ has yet been discovered for the sense of tem- 

 perature. It is very curious to be assured by experiment 

 that there are "hot" spots and " cold" spots on the fingers. 

 If a copper point, of the temperature of the skin, be applied 

 to a cold spot on the finger, a cold sensation is excited ; 



