I made a chair repair the other day, and when getting furniture clamps out, I uncovered an old Hargrave C T Tool Co bar clamp.
Although rusty, it is in good working order. 30" bar with lots of info. Canadian patent # 1638848 of 1927. Parts are numbered also.

Those clamps are handy! we have a few to glue things back together.
A pic of some in action on a 1937  RCA console radio.

Here is some Hargrave history by a family member.
http://theclampguy.info/hist_hrg.htm

I wonder about the Canadian Pat designation, since the above history lists it as :
1,638,848 for Clamp
Patent Number   1,638,848
Date Applied For   unk
Date Issued   1927 08 16
Issued to   Hargrave
Location   Cinncinati OH

And confirmed by Datamp- http://www.datamp.org/patents/displayPatent.php?id=35408

Papaw I think you are confused. That is the US patent. The Canadian patent is    CA 268829     which you can see here. http://www.ic.gc.ca/opic-cipo/cpd/eng/patent/268829/summary.html?query=(hargrave%2c+bar+clamp)+%3cAND%3e+(ISD%3e%3d1927-01-01)+%3cAND%3e+(ISD%3c%3d1928-01-01)&start=1&num=50&type=boolean_search

click on documents and scroll to the bottom of the page

I did see that in my research. Thanks !
Seems to be valuable according to "Sold " listings on Ebay.

Yeah if your bar clamp is a Hargrave, Bessey or Wetzler it definitely has value.