(Wombling shall be an irregular series of posts about interesting stuff members of Team Spinneyhead find which, as the Wimbledon commoners would have it “the everyday folks leave behind”.)
This interesting piece of kit is a Field Clinometer Mark III. Harry found it at the tip whilst scouting for bikes and bike parts. Research (primarily here and here) revealed that it was a device used in the aiming of artillery pieces.
The clinometer was placed on the barrel as it was elevated and the swing arm used to measure the angle. The arm can be adjusted by degrees. The sprung shoe still works well- pull it back to disengage the teeth then move the arm into position.
For greater accuracy the arm has a slight bow so the spirit level can be slid along it to get measurements at the minutes level.
Sadly the spirit level itself has been smashed. Otherwise the clinometer would still work almost as well as when it came out of the factory over a century ago.
The device was built in the Soho M&S Instrument Works in 1906 and was numbered 869. This is one of those “What tales it could tell” objects.
Unfortunately neither Harry nor I have access to any artillery, so the clinometer’s going on eBay to find a good home. (Note The auction has now ended and the clinometer shall be making its way to a new home soon.