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| Mystery Measuring Stick |
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| steampunkpete:
--- Quote ---Minutes or seconds was in response to Rob's suggestion of degrees - 60 seconds in a minute, 60 minutes in a degree ..... --- End quote --- Understood - I was signifying agreement rather badly. vtsteam makes a good point about the vernier appearing to be a linear scale in relation to a solution that one would instinctively expect to be non-linear. However, the gun might be subjected to calibration at a single fixed range, in which case a linear scale could / would be adequate. A couple of things though: The quality of this thing (whatever it is) is excellent. In itself it is of adequate integrity to survive fitting to an artillery piece. What isn't rugged is it's mounting arrangement; it would not be suitable for a permanent attachment to anything in field conditions, hence my belief that it is for calibration only. |
| awemawson:
If you look up that book I quoted they go into great detail regarding sight calibration, particularly in fixed locations. It was while reading up on the 'Palmerston Forts" that I came across it, as I wanted to know how they managed to sight fixed pieces that were behind often a natural earth berm so not in view of the target. There are illustrations of attachments to the side and top of RML's (Rifled Muzzle Loaders) that probably are a forerunner of the device that you have |
| S. Heslop:
I asked an artillery guy I knew if he recognized it, and he didn't, but said possibly part of a gunners quadrant (but doubtful). Did a bit of searching on google image search and found this diagram. From this website of a 'tangent backsight'. It somewhat resembles the deflection adjustment on the left one. Did alot more searching but I couldn't find a photo of the same device posted in this thread, but I don't think it'd require an aperture like a rifle sight since (as far as I know) when sighting artillery they line it up horizontally with posts driven into the ground. |
| vtsteam:
I'm willing to believe it's a sight, but it raises a lot of interesting questions for me. If it is a linear scale with vernier, and the angle is relatively small (minutes of arc) I can see that it might serve an angular purpose since a small range of angle approximates a linear scale better. But that would mean that the entire range of the sight would be only plus or minus one degree, which seems like a very small angular range for a gun sight. If it was degrees instead of minutes, then it really would be an inaccurate measurement if you impose a linear scale on an angular range of 120 degrees total (+60 to - 60) If it is like the adjustment on a peep sight adjusmtent to bring it into conformance, a small (minute or second) amount of adjustment would make sense because it is in relation to a second sight point on the barrel, but isn't that usually "clicks"? in other words, relatively arbtrary. Why then would it be necessary to have an inconvenient numbering system like 60 instead of 50 unless it was important to relate it to an angular numbering system? The 30 mark and 60 range makes me think it is angular, but the range seems too be either too small, or too linear for sighting. I'm sure there is an explanation, just curious how it works and why (as usual!). |
| vtsteam:
Wouldn't a wide blade on top like that tend to block what you are aiming at to a dangerous degree? If there's movement laterally or behind, how can you tell? |
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