by Korn, Arthur
1907. Korn, Arthur (1870-1945). Über die Versuche mit Bildtelegraphie zwischen München und Berlin vom 15. April bis 15. mai 1907. Offprint from Elektrotechnischen Zeitschrift 33 (1907). 4pp. Text illustrations. 270 x 192 mm. Original printed wrappers. Lightly creased but very good. Presentation Copy, inscribed on the front wrapper: "Überricht vom Verfasser." From the library of physicist Henri Becquerel (1852-1908), with his characteristic gummed docketing label on the front wrapper. First Edition, Offprint Issue. Korn invented telephotography, the first practical method of scanning and transmitting images over electrical wires. His system used a light-sensitive selenium photocell to convert the different tones of an image into a varying electrical current; at the receiving end the transmitted image was reconstituted and recorded on photographic film. Korn invented his device in 1902, but his first machines were impractical as they took as long as 12 hours to transmit images. By 1907, the year he published the present paper, Korn had improved his machines to the point where they could transmit a 13 x 18 cm. photograph in 12 minutes; some of these images and their transmission times are included in this paper. In April 1907 Korn's equipment was put into regular service for transmission of newspaper photographs between Munich and Berlin via telegraph circuits. .
(Inventory #: 44400)