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T. Bergner, April 2, 1872, no.125,115
Details
Patent model - an improvement in parallel rulers
T. Bergner, April 2, 1872, no.125,115
comprising a triangular rule (one corner broken off) and flat plate, both of a brown resinous compound, attached via a sliding slot with screw clamp, the plate with sprung mounting beneath for a straight rule (lacking) and a pawl above with adjustment screw, light spring and push button for moving the rule, the plate engraved Theodore Bergner's Parallel Rule, with original manuscript patent tag and the remains of a second original tag, also with a photocopy of the patent office document
5½in. (14cm.) wide
T. Bergner, April 2, 1872, no.125,115
comprising a triangular rule (one corner broken off) and flat plate, both of a brown resinous compound, attached via a sliding slot with screw clamp, the plate with sprung mounting beneath for a straight rule (lacking) and a pawl above with adjustment screw, light spring and push button for moving the rule, the plate engraved Theodore Bergner's Parallel Rule, with original manuscript patent tag and the remains of a second original tag, also with a photocopy of the patent office document
5½in. (14cm.) wide