BEGINNINGS OF THE TELEPHONE 179 



neighborhood of the membrane it would be thrown into vibra- 

 tion and cause the steel reed to move in a similar manner, 

 occasioning undulations in the electrical current that would 

 correspond to the changes in the density of the air during the 

 production of the sound; and I further thought that the 

 change of the density of the current at the receiving end would 

 cause the magnet there to attract the reed in such a manner 

 that it should copy the motion of the first reed, in which case 

 its movements would occcasion a sound from the membrane 

 similar in timbre to that which had occasioned the original 

 vibration. 



The results, however, were unsatisfactory and dis- 

 couraging. M}^ friend, Mr. Thomas A. Watson, who assisted 

 me in this experiment, declared that he heard a faint sound 

 proceed from the telephone at his end of the circuit, but I 

 was unable to verify his assertion. After many experiments 

 attended by the same only partially successful results, I 

 determined to reduce the size and weight of the spring as 

 much as possible. For this purpose I glued a piece of clock 

 spring about the size and shape of my thumb nail, firmly to 

 the center of the diaphragm, and had a similar instrument 

 at the other end; we were then enabled to obtain distinctly 

 audible effects. I remember an experiment made with this 

 telephone which gave me great satisfaction and delight. 

 One of the telephones was placed in my lecture room in the 

 Boston university, and the other in the basement of the 

 adjoining building. One of my students repaired to the 

 distant telephone to observe the effects of articulate speech, 

 while I uttered the sentence, ^^Do you understand what I 

 say?" into the telephone placed in the lecture hall. To my 

 deUght an answer was returned through the instrument itself, 

 articulate sounds proceeded from the steel spring attached 

 to the membrane, and I heard the sentence, ''Yes, I under- 

 stand 3^ou perfectly." It is a mistake, however, to suppose 

 that the articulation was by an}" means perfect, and expectancy 

 no doubt had a great deal to do with my recognition of the 

 sentence; still, the articulation was there, and I recognized 

 the fact that the indistinctness was entirely due to the imper- 

 fection of the instrument. I will not detaU the various stages 



