In A Nutshell Antiques and Interiors has dated this piece to the 1910s.

This example is made in brass and is stamped "Troughton & Simms, London, 1915. No.1638" and it has the military crows foot.
It comes in a stitched leather case which also carries the military crows foot and it is stamped "M.D.S. London. 1941".
The clinometer is in good condition for its age.
There are some general signs of age and use and minor light knocks and surface but nothing untoward. The leather case is in good order with a nice patina.
The best description comes from the photos so please look at them all carefully and if you have any questions just ask.
Tracked UK Delivery £8
In A Nutshell Antiques and Interiors has dated this piece to the 1910s.
Selling good quality victorian, georgian and earlier furniture, accessories & decorative items. Ashburton, devon. LAPADA member
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In A Nutshell Antiques and Interiors is a registered member of LAPADA CINOA