On Wed, 22 Aug 2007 10:45:52 -0400, Fred Fowler III
wrote:

Hey all,

Found some old precision tools at a Sandwich, MA antique store. I
thought they might be nice for my fathers old tool collection (x-mas
present).

Was hoping someone in this group could give me a rough dating of the
pieces. I reckon it is hard to do just with pictures, but anything
helps... I have pictures he

http://picasaweb.google.com/fredfowler3

The internal divider style caliper is one design I have never seen
before, and really well finished (captive spring and cross plate).
Marked Pat. 1863, but wondering how old the tool really is? Civil war
era seems a bit old???

Some musings...

Most patents are only good for a period of 20 years max or
possibly less due to application and grant dates. So there
is no good reason to stamp the patent date on an item if the
patent has long since expired. But I'm sure people have done
so for who knows what reason. The patent on your item
appears to be for the method of adjusting the caliper using
both right and left hand threads and a new type of nut to
take up wear/slop. See:

http://www.datamp.org/displayPatent.php?id=13093

http://www.google.com/patents?vid=39281

One would think that it was made sometime between 1863 and
1883 going on the length of patent logic (shrug).



The inside /outside caliper from Starrett is also one I have never
encountered. Antique shop says it dates from 1896 or so, but I am
somewhat suspect. Still it's a nice piece. Any ideas?

Seeing Starrett is still in business the suggestion to
contact them is worth a try.

--
Leon Fisk
Grand Rapids MI/Zone 5b
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