Two devices, as of Fig. 2, adjusted one ahead of the other and to a relatively short distance, they can be used to transmit and to receive acoustically? it wants to say, without the telephone (50) and also without cooperation of the selenium plate (40). Then, to transmit, the operator, after putting in functioning the fan (11) and the light of 18 (fig.2), will speak through one of nipples 9 or 10, closing the other. To receive, he will stop the fan, and he will take nipples 9 and 10 to the ears. The fan alone is used in the transmission. The device, in this I try, works established in assaz known principles of the conjugated mirrors: I find thus that the addition of certain qualities of light improves the effect, in the transmission as in the reception. Perhaps the thus considered device does not have great commercial value: but demand I it for that, to say well, it constitutes the transmitter of my telephone without wire, in the same way that my cell of selenium, here described, constitutes its receiver. In my telephone without wire? that is, with the cooperation of my fotofnicos devices? my actinic clear light is absolutely necessary.

I say? ' ' Clear light actnica' ' , that is: composed light of clear radiations and actinic radiations, as the one that is produced by an arc light bulb, or for a blue glass in front of a common luminous source. To transmit to a long distance I give to preference the generated composed light in an arc light bulb. To produce rays or violet light actinic, I can external adjust to intern or to 17 baffle a fine done difana substance film appropriate. Thus, in the high one of pipe 15 a telephonic receiver is mounted (50), on to the home loop (55), also contends a battery (51) and including the selenium cell (40 -50).