This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Ramsden's zenith telescope. en The zenith telescope constructed by Jesse Ramsden in Used to determine the latitude of stations of the Principal Triangulation of Great Britain An Introduction to Practical Astronomy Volume William Pearson other versions PDold Uploaded with Surveying Ordnance Survey Jesse Ramsden