Clinometer.

W. Newman & Co.
Calcutta
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28411 2

Clinometer with spirit level and elevation protractor which is used in surveying.
The object is marked 'W. Newman & Co. Calcutta' who made an improvement on the Abney design. Elliott Bros also registered an "improved clinometer and spirit level combined" in December 1870 based on "the old form as originally designed by Lieutenant Abney".
Stamped on the body is the No. 28411 which is possibly the serial no.
The item is part of the Ron Howard collection.