Trough Compass with Case, 1916
![Image: Trough Compass with Case, 1916](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/full_width/public/000824-Trough_Compass_%282%29.jpg?itok=C0P_1tP5)
Detailed Description
The storage case has a sliding lid. The compass is marked Troughton & Simms Ltd, London, 1916, No.9214. A trough compass is used with either a plane table or a theodolite. The needle is a long magnetized bar of steel which is pointed at both ends.
Object ID: USGS-000824
Sources/Usage
Public Domain.