Abstract :
REMOTE indication is, in general, the transfer of information or intelligence from one point to a remote point in a semipermanent form which may be visually observed. A variety of means can and have been used to accomplish such a purpose. Information can be sent from one place to another simply by moving a long string or cable, rotating a long flexible shaft, changing pressure in a hydraulic or pneumatic line, changing the characteristics of an electric circuit, as well as by methods involving thermal and optical devices. The fields of telemetering and visual recording are well-known branches of remote indication. Automatic control systems and computing mechanisms depend on remote indication for their source of intelligence.
