Inventors at work, with chapters on discovery (1906)
Iles, George, 1852-1942 · New York, Doubleday, Page & company · leaf 392
CALLING 6 ON THE AUTOMATIC TELEPHONEAutomatic Electric Co., Chicago. CHEMICAL TRIGGERS 337 such as that of a village with ioo instruments, we may readilyunderstand the main principles of the method. Let us supposethat No. i of our instruments is at the Post Office, where thePostmaster wishes to…
Inventions · Inventors
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![An illustration from Telephones and telegraphs: 1902 : [and Municipal electric fire alarm and police patrol systems] (1906)](https://img.insideoutlibrary.com/img/200/ia-cu31924022817674-68-28.webp)
![An illustration from Telephones and telegraphs: 1902 : [and Municipal electric fire alarm and police patrol systems] (1906)](https://img.insideoutlibrary.com/img/200/ia-cu31924022817674-46-8.webp)
