Google Patents turns up a handful of patents issued to "G. I. Mix"
and "Garry I. Mix" between 1857 and 1874, all but one related to
the manufacture of spoons. The odd one out is a design for a
water cooler.
Yet another Google search (Google Books this time) located
a couple of photos related to Mix. One's an undated photo
of the exterior of the factory on Main Street in Yalesville.
The caption mentions that John Mix, G. I. Mix's father,
made bayonets nearby from 1810 to the 1830's. Tony, are
your framing chisels old enough that he could be the source
of the "JW" mark?
The second's a group photo, said to be from the 1880's, of
the Mix employees, showing about 50 or so people.
Here's a link:
http://tinyurl.com/34294t
If it doesn't take you right to the page, scroll down to
page 52. And in case the link rots, the photo's are in
_Images of America: Wallingford_ by the Wallingford
Historical Society (1999, Arcadia Publishing). On the
previous page are a couple of Jennings & Griffin photos.