170 PLEASANT WAYS IN SCIENCE. 



be perfected to such a degree that words uttered on the 

 American side of the Atlantic will be heard distinctly after 

 traversing 2000 miles under the Atlantic, at the European 

 end of the submarine cable so that Sir W. Thomson 

 at Valentia could tell by the voice whether Graham Bell, 

 or Cyrus Field, or his late colleague Professor Watson, 

 were speaking to him from Newfoundland. Yet a single 

 wave of those which toss in millions on the Atlantic, rolling 

 in on the Irish strand, would utterly drown the voices 

 thus made audible after passing beneath two thousand 

 miles of ocean. 



Here surely is the greatest of telegraphic achievements. 

 Of all the marvels of telegraphy and they are many none 

 are equal to, none seem even comparable with, this one. 

 Strange truly is the history of the progress of research 

 which has culminated in this noble triumph, wonderful the 

 thought that from the study of the convulsive twitchings of 

 a dead frog by Galvani, and of the quivering of delicately 

 poised magnetic needles by Ampere, should gradually have 

 arisen through successive developments a system of com- 

 munication so perfect and so wonderful as telegraphy has 

 already become, and promising yet greater marvels in the 

 future. 



The last paragraph had barely been written when news 

 arrived of another form of telephone, surpassing Gray's and 

 La GOUT'S in some respects as a conveyor of musical tones, 

 but as yet unable to speak like Bell's. It is the invention 

 of Mr. Edison, an American electrician. He calls it the 

 motograph. He discovered about six years ago the curious 

 property on which the construction of the instrument 

 depends. If a piece of paper moistened with certain 

 chemical solutions is laid upon a metallic plate connected 

 with the positive pole of a galvanic battery, and a platinum 

 wire connected with the negative pole is dragged over the 

 moistened paper, the wire slides over the paper like smooth 

 iron over ice the usual friction disappearing so long as 

 the current is passing from the wire to the plate through 



