Another Clinometer

[Birdseye]

Same principle as the tried and true gunner's quadrant, set the angle, affix to appropriate surface of gun, adjust elevation until the bubble in the level is centered.

Unmarked except for the number 156 under the dial. Appears to be painted aluminum. Case is leather and unmarked. Calibration in degrees.

The seller suggested that it was British and could be as early as the Boer War. That sounds a bit optimistic to me. Anybody seen one like this or have any other thoughts on the matter?

 

[Birdseye]

Sorry for the shadows.

 

[Howitzer155mm]

This is a mortar quadrant (American)/clinometer (British) and this is a very common design. I'm not sure which particular country this mortar quadrant comes from. Similar models have been manufactured in the following counties: China, Croatia, France, Finland, Hungry, Italy, Poland, Romania, Russia, Hungry, and Yugoslavia.