Mirando por encima este libro me he encontrado con algunos de los manuscritos y esquemas de Graham Bell del teléfono. Resultan interesantes por mostrar, quizá, los primeros esquemas o esbozos para la transmisión electromagnética del sonido, lo que cambiaría por completo nuestra idea del mismo.

Very interesting are the sketches of Figs. 6.34 , 6.35 and 6.36 : they are sketches and manuscripts of Alexander Graham Bell (1847–1922) and are relative to the invention of the telephone. Figure 6.34 , particularly, represents a schema of an experience of transmission between Mr. Bell and Mr. Watson, in two different rooms with communication doors closed. Mr. Bell shouted the following sentence “Mr. Watson come here. I want to see You”.Figure 6.35 is relative to another schema of experiments, with the signature of Bell (Boston, May 1876). There is written “As far I can remember, these are the first experiments made of my telephone.” Very interesting, from the personal point of view, is the document in Fig. 6.36 : it is a communication of Bell to his parents Alexandre Melville Bell and Eliza Bell (May, 5, 1876).

Fig. 6.34 Schema of an experiment of transmission by Bell. P is the brass pipe and W the platinum wire, M the mouth piece and S the armature of the receiving instruments

Fig. 6.35 Another schema of experiments, with signature of Bell (1876)

Fig. 6.36 Communication of Bell to his parents about his successful experiments