simple variation compass
Datelate 19th-early 20th Century
Inventory Number1998-1-1427
ClassificationVariation Compass
Subject
Maker
American
?
Cultural Region
Dimensions1.7 x 9.9 x 2.8 cm (11/16 x 3 7/8 x 1 1/8 in.)
Material
DescriptionA simple, rectangular wooden box with a compass needle (blue and white) inside stretching from one end to the other. On the top and bottom, a white section with a marking in the middle is the only semblance of a scale.
Glass cover and two brass screws for bracket on side.
Glass cover and two brass screws for bracket on side.
Signedunsigned
FunctionThis is a very rudimentary form of a trough or variation compass. It was probably used to determine the magnetic north and to align and draw lines parallel to the earth's magnetic field on a plane table.
Since there is no scale, it could not be used directly to determine magnetic declination or variation.
Since there is no scale, it could not be used directly to determine magnetic declination or variation.
C. F. Casella & Co. Ltd.
Date: circa 1920
Accessories: black brass case
Object number: 5111
C. F. Casella & Co. Ltd.
Date: circa 1920
Accessories: leather carrying case; long leather strap with brass loop at end
Object number: 5100
