1. telegraph, facsimile A telegraph for transmitting facsimiles of drawing or writing. The methods employed involve the synchronous rotation of two metallic cylinders, one at the transmitting end, the other at the receiving end.
On the transmitter the design is drawn with non-conducting ink. A tracer presses upon the surface of each cylinder and a circuit is completed through the two contacts. In operation a sheet of chemically prepared paper is placed over the surface of the receiving cylinder. The two cylinders are rotated in exact synchronism and the tracers are traversed longitudinally as the cylinders rotate. Thus a number of makes and breaks are produced by the transmitting cylinder, and on the receiving cylinder the chemicals in the paper are decomposed, producing marks on the paper exactly corresponding to those on the transmitting cylinder.
Definitions of telegraph, facsimile
