ACOUSTIC TELEGRAPHY. 
3 i 
electricity which, passing through the line to the corresponding 
station, excite the magnetism of a magnet in the circuit and 
thus set into vibration a plate of iron like that against which 
the original voice was directed. This iron plate speaks to the 
hearer, and speaks so distinctly that if three persons speak or 
sing all together at the other end, their voices can be distin¬ 
guished and are heard as if they were themselves present. Is 
not this the crown of the edifice ? We cannot but admire the 
genius of the inventors who have given us the means of 
speaking with friends at a distance, and of hearing the sound 
of familiar voices or the loved accents of a person w 7 ith whom 
we can converse in spite' of separation. 
And what may we not yet expect from the telegraph and 
the applications of science, especially that of electricity, the 
marvellous agent that interpenetrates the wdiole of nature ? 
If, instead of making jokes at Charles Bourseul in 1854, when 
he proved the possibility of a method of correspondence that 
has now been realised, people had encouraged that young 
inventor, whose idea was five years afterwards put into 
practice by Reiss, we should doubtless have had the telephone 
invented in France. The future will bring us many other 
wonders, for which, however, we are now prepared. Already, 
Edison’s electro-motograph or motophone, in which a supple¬ 
mentary force is put in action by suitable contrivances, 
magnifies the sound of the human voice, and so increases its 
intensity as to make it heard by a large audience. 
The telephone companies have not been long established in 
France, and the improvements they have introduced are but 
slowly making way with the mass of the public, which does 
not always perceive clearly its own interest. The monopoly of 
European governments is tending to disappear, and should 
not be regretted, for it has often weighed heavily on inventors, 
and proved an obstacle to the development of great inventions. 
The vast development of telegraphic inventions in England 
and in America is due entirely to the absence of this monopoly ; 
and although England has adopted the doubtful policy of 
appropriating the internal network of telegraphs to the Post 
Office by buying up the great companies of the United King¬ 
dom, she has never dreamed of taking out of the hands of 
private companies that immense system of submarine tele- 
