|Description||Incomplete theodolite. Two fixed sight vanes are mounted to the horizontal circle, which is attached to the tripod assembly through the socket. Rotating compass and alidade with vernier blades in center. Signed "B. Chandlee Nottingham" along outer circle. Analysis of the alidade by a Scanning Electron Microscope in 2007 revealed that it contained silicon, most likely originating from a mixture of silicon bronze, a product that was not developed until the late 19th to early 20th century. Therefore, the alidade is not original to the piece.|
Benjamin Chandlee founded Chandlee & Sons in Nottingham, Maryland around 1770, specializing in clocks and scientific instruments like this one. Theodolites, like circumferentors, were used for taking bearings in surveying. The large outer circle and inner arms that rotate around it indicate that the instrument is incomplete, missing its second pair of sighting vanes.
|Dimensions||H-6.813 Dia-11 inches|
|Dimension Details||Diameter includes sight vanes|
|Credit line||American Philosophical Society. Gift of Penrose Hoopes, 23 June 1975.|