ANNIVERSARY ADDRESS. 5. 
' a solid bar of iron for core, which is connected at one end by a 
thick dise of iron to an iron tube surrounding the coil and bar. 
The free circular end of the tube constitutes one pole of the 
electro-magnet, and the adjacent free end of the bar core the 
other. A thin circular iron dise, held pressed against the end of 
the tube by the electric-magnetic attraction, and free to vibrate 
through a very small space without touching the central pole, 
constitutes the sounder by which the electric effect is reconverted 
into sound. With my ear pressed against this disc I heard it. 
speak distinctly several sentences. * * * I need scarcely 
say I was astonished and delighted; so were others, including 
some judges of our group who witnessed the experiments and 
verified with their own ears the electric transmission of speech. 
This, perhaps, the greatest marvel hitherto achieved by the 
electric telegraph, has been obtained by appliances of quite 
a homespun and rudimentary character. With somewhat more. 
advanced plans and more powerful apparatus, we may con 
fidently expect that Mr. Bell will give us the means of making 
voice and spoken words audible through the electric wire to an 
ear hundreds of miles distant.” 
Inspired by so flattering a verdict, Mr. Bell returned to his. 
experiments with renewed enthusiasm, and in 1877 he subjected 
his instrument to a series of experiments in America, of which, 
if not. greatly exaggerated, the accounts we have received are 
perfectly astounding. We read of concerts being heard at 
places forty-three miles distant, and telephonic communication 
being carried on between Boston and New York, a distance of 
250 miles. The first practical application of the telephone is 
stated to have been made in May, 1877, by the Water Board of 
Cambridge, in the State of Massachusetts, who established tele- 
phonic communication with the waterworks at Freshpond, in 
order to facilitate the sending of messages. Now more than 500 
houses in New England hold telephonic communication, and 
more than 3,000 ph daloghonee are said to be in operation in the 
United States. 
