A Gyro Compass uses the stability of a gyro to maintain a sense of direction in a manner similar to a Magnetic Compass.
Although gyro compasses were fairly new technology in the World War I era, they proved valuable in Fire Control applications and to act as navigational compasses in conditions where a magnetic compass would be grossly influenced, as in a submarine.
The British found it desireable in early 1914 to introduce a paper form S. 1777 to serve as a log to track the function and adjustment of each gyro compass in inventory.
- Admiralty Weekly Order No. 915 of 27 Feb, 1914.