Scrimshaw, wood inlay, compass point or sextant?

[Skinny]

Here's my two cents. This thing looks a little small to me to be a carpentry tool used in building ships. Those beams and planks were huge. It also strikes me as a little too fancy, and not beat up enough to have been really used  for any kind of rough carpentry work. I could be wrong. Does an architect use anything like this?

If I had to guess a time period for this, I would have to go OLD. Early sixteenth century? I base this guess on the fact that the measurments are obveously not close to standard (as I would expect from something later) and on the style of the carvings. Those numerals look consistant with how people at that time wrote their numbers. The five is a dead ringer.

I would expect more patina on the wood, but i'm sure its an exotic wood, and i'm no expert on how those woods age. Whoever used this was no pauper. This is a finely crafted piece made of rare materials. I would love to know where this came from and what it was for!

[regularjoe2]

I think it's actually a scaling protractor used by wood carvers (cabinet-makers) , used in conjuntion with (metal or metal-pointed) dividers .

Please correct me if I'm wrong !

Very nice little tool , ppgs .

It's a keeper !

[hosman321]

This beautiful tool is just amazing, you have an amazing piece of history. Reminds me of the sundial that was on Pawn Stars. Same style, material and age. Did anyone else see that episode? I can try to find the link for those who haven't. Here's the dial, gotta find the video.

http://www.thepawnshow.com/?s=sundial
Found it, here's the videos.
http://www.youtube.com/watch?v=pIC4BZZZ0DE <---intro
http://www.youtube.com/watch?v=6ID50WbWK8M <---conclusion.

Just to show the style of that age. -> http://cgi.ebay.com/SILVER-GILT-AUGSBURG-COMPASS-SUNDIAL-17TH-18TH-CENTURY-/140362649864?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item20ae441108

[cogar]

How about it being an octant or quadrant

[waywardangler]

The measurements on the inside arc piece are divided by blocks into fourths and further divided by dots into eigths.  The scale goes from 0 to 12.  The 'rule' does not open fully to make a 90 degree measurement so this being an angle finder can be ruled out IMO.  The measurements on the outside rules appear to be 2cm = 10 with graduations of tenths which makes zero sense.  The measurements  do not equal inches going by the tape laid next to the markings. I have looked through all my books and the web and not much comes close to what this was used for.  I do not think it is a scribe missing its' points as there is nothing to lock the center arc to keep it from opening/closing when in use. I have looked at octant, quadrant, sector, bevel finder, protractor, etc.  This must have been a specialized tool for some trade and it would be very helpful if we knew what ppgs' grandfather did or his grandfather's grandfather did etc.  Judging by the decoration and carving and from what I have gleaned, I think it is 18th century or even older as Skinny mentioned and also European but not British. The hat measuring device (French) comes close as the graduations on the arc are 1-7 but the band is missing.  It is one beautiful tool and another conundrum to be solved.

[Skinny]

Are we sure it doesn't (or didn't) open up to a ninety degree angle?
I haven't seen a pic of it fully open. When it's closed, it looks like (at the top) two forty fives, which should allow for a ninety when fully open. Of course, I wouldn't be at all suprised if the curved rule is bowed from age that it would hang up near the end and not allow for the piece to open all the way.

When this was used, it should have been able to open far enough for all of the measurment lines on the curved ruler to be on the inside of the angle, and for the hinge to be fully closed.

ppgs, will this thing still open all the way, or is it open as far as it will go in the pics?

[waywardangler]

This is the best rendering of what it would look like opened up.  The markings on the arc would be short and the arc would also be short.  The arc should extend past the left arm or there would be problems in use.  The arc end is ragged so it may have been broken but the markings also stop so it appears it was made that way.

[Skinny]

This is the best rendering of what it would look like opened up. The markings on the arc would be short and the arc would also be short. The arc should extend past the left arm or there would be problems in use. The arc end is ragged so it may have been broken but the markings also stop so it appears it was made that way.

Not to be a pain in the butt, but I don't really understand what your saying. The representation you just showed depicts an angle that's MORE than ninety. To get a to ninety, just draw your line from the pin (in the hinge) to the very last mark on the curved rule. You may be right that it would then go on to open even further, but I think myself that it would have stoped around the ninety degree mark. I would say that opening up to a full square leaves this piece in the running as an angle finder.

I wouldn't say the arc would have to extend past the left arm, as long as it doesn't come completely out of it when its open. It doesn't look like it would come out to me, but without being able to open it all the way, its tough to say.

[waywardangler]

Skinny, my reply was lost (said I double posted but it is not here) so I see what you are saying.  My original crude lines are past 90.  I have monkeyed with the image so the vertical goes straight up from the first vertical line on the bottom rule arm.  It cuts the arc at about the last line which would be 12.  If this were an angle finder I would expect this number to be 9.  I may be missing something.  The key to this is what do the measurements on the arc measure?  The arc arm stays in the vertical so that is good.

[Skinny]

It's definitly an angle finder. I've attached a picture of a modern device that would acomplish the same task, although it's design is different. The mathematics are a complete mystery. A full circle would be called 480 degrees according to this device. They're using no forms of measurment that i've ever seen. This is one of the reasons that I put an age estimate of early 1500's on this thing. Some sort of local measuring system. European for sure. This is a unique treasure if you ask me. Probably on of a kind.

[waywardangler]

All the measurements on this are baffling.  Skinny, are you familiar with cartography (I am not)?  I am wondering what ancient map maker's used.  Would these numbers mean anything with longitude or latitude or degrees or ?  I am familiar with the angle finder you posted but these markings on this piece are a wonderment.

[Skinny]

All of the old maps i've seen (with longitude and latitued marked on them) used the same standard system. The poles were ninety degrees and everything went from there. I couldn't say this device wasn't used in making or interpreting maps, but I can't understand how it could have been used in that purpose.

I would just have to conclude that this thing is marked with some private, or local, or even regonal form of measurement that has long ago ceased to be used. There's no telling how old this thing is. I would just have to advise ppgs to try to consult some real experts, and if you do find anything out, let us know!

[talesofthesevenseas]

I think contacting that compass museum would be a good way to determine it's specific use and age. We've got the general idea, but the specific industry is still a mystery and I think it is going to need a specialist in that field to say exactly how it was used. (My two dubloons worth there!)

[syl]

I think I know what this is. It's a carpenters tool used in framing wood roofs. The reason the numbers on the curved part don't make sense is they aren't degrees. The are numbers used to mark or measure roof pitch. Pitch is measured in inches of rise in 12 inches of horizontal run. If you place the lower arm along the bottom edge of a board and then set the swing arm at 6 and then draw a line along that arm you would have a 6 and 12 pitch. Once that line is established you can then draw your top cut and bottom cut on your rafters. The same system is still used today although there are better tools, like framing squares, speed squares and so on. This piece looks European in origin.

[talesofthesevenseas]

You might just be right on that Syl! Good call! All the way straight up comes out at 12/12!