Finding this at the M-WTCA Peach Meet in Madison, GA just about justified the 7 hr. drive.
This must be the smallest vise that Prentiss ever made. The jaws measure just 1 1/4 in. wide and have a maximum opening of 1 1/8 in. Overall length is 4 3/8 in.
One side is marked "P.V. Co. N.Y." and 300 under that. The other side has an anchor symbol followed by line, which I assume means Anchor Line. Unfortunately this doesn't mean anything to me.
Interestingly, this is a patented vise, although DATAMP shows it as having never been made.
If you are interested, the patent information is below.
http://www.datamp.org/patents/displayPatent.php?number=703376&typeCode=0As you can see, the vise is manufactured just as the patent shows.
Any additional information would be appreciated.
Mike