An antique hand lens for viewing nature - insects, leaves, etc. It was shown to me by
a friend who inherited it from his brother, who was an avid collector of such things.
This hand lens is made of brass, with a pin to mount the object of interest on.
The mounting pin slides to and from the lens for focusing then stabilized
with the brass screw beneath it. The handle is ivory. The case was made
by a man who died in the late 1800's.
It's actual age is not currently known but we know this hand lens is likely older than the US as a country.