LOVELY EARLY 1843 CRAFTSMAN-MADE TRAMMEL POINTS & RULER

Gorgeous patina on a 28" graduated keeper rule which has imperial measurements on one side and another unusual scale on the other. It is close to a metric scale but definitely off by a bit although numbered 10, 15, 20, 25 etc etc like metric.  Very early and hand stamped and graduated. '1843' stamped on one trammel. Trammels are about 6" in height. Fascinating piece.