. Telephones and telegraphs: 1902 : [and Municipal electric fire alarm and police patrol systems] . TELEPHONE CENTRAL OFFICES AND CENTRAL OFFICE DISTRICTS IN NEW YORK CITY JANUARY 1, 1894; 21 CENTRAL OFFICES AND 14,528 TELEPHONES. TELEPHONE CENTRAL OFFICES AND CENTRAL OFFICE DISTRICTS IN NEW YORK CITY JANUARY 1, 1905; BO CENTRAL OFFICES AND 180,801 TELEPHONES. OHAPTEE XL HISTORY AND DEVELOPMENT OF TELEPHONY. Early development.—The history of the telephone,like that of the telegraph, as indeed of any other greatinvention, is full of conflicting claims as to priorityof discovery. But it is a fac
. Telephones and telegraphs: 1902 : [and Municipal electric fire alarm and police patrol systems] . TELEPHONE CENTRAL OFFICES AND CENTRAL OFFICE DISTRICTS IN NEW YORK CITY JANUARY 1, 1894; 21 CENTRAL OFFICES AND 14,528 TELEPHONES. TELEPHONE CENTRAL OFFICES AND CENTRAL OFFICE DISTRICTS IN NEW YORK CITY JANUARY 1, 1905; BO CENTRAL OFFICES AND 180,801 TELEPHONES. OHAPTEE XL HISTORY AND DEVELOPMENT OF TELEPHONY. Early development.—The history of the telephone,like that of the telegraph, as indeed of any other greatinvention, is full of conflicting claims as to priorityof discovery. But it is a fact beyond dispute thatin 1876, at the moment of Bells invention of hisspeaking telephone, there was not a single operativetelephone in the hands of the public anywhere in theworld. The whole art and industry of which this re-port makes record dates from 1876-77. As early as1837 Page discovered that an iron bar when magnet-ized and demagnetized at short intervals of timeemits sounds, due to the molecular disturbances of themass. Reis, in Germany, utilized this fundamentalprinciple and constructed apparatus for the trans-mission of sound to a distance by electrical to that the idea of telephony had been definedb
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Keywords: ., bookcentury1900, bookdecade1900, booksubjecttelephone, bookyear19
