Boxwood Button Gauge by SMALLWOOD - Caliper Rule
A scarce and little used SMALLWOOD button gauge caliper rule.
The measuring of buttons was standardised in the late 18th century by a Mr Matthew Boulton of Birmingham. This new standard measured button in lines with 40 lines to the inch.
Boxwood with brass fittings.
Marked 'I&D SMALLWOOD MAKERS B'HAM. ENGLAND' on one edge.
The boxwood body is graduated into eighths and sixteenths.
The brass caliper slide is graduated into 40ths/inch or 40 lines per inch.
Matching '888' stamps on the back of the caliper slide and within the recess.
11/8 inches wide, 31/2 inches overall length.
A very nice example.