'Photochronograph' definitions:
Definition of 'Photochronograph'
From: GCIDE
- Photochronograph \Pho`to*chron"o*graph\, n. [Photo- + chronograph.]
- 1. (Physics) An instrument for recording minute intervals of time. The record is made by the power of a magnetic field, due to an electric signaling current, to turn the plane of polarization of light. A flash, coinciding in time and duration with the signal, is thus produced and is photographed on a moving plate. [Webster 1913 Suppl.]
- 2. (Astron.) An instrument for the photographic recording of star transits. [Webster 1913 Suppl.]