Empire datum frame rule
 Catalogue Number: 2237 Empire datum frame rule Category: Equipment Sub-Category: Dispensing tool Year Of Publication/Manufacture: c 1950 Time Period: 1940 to 1999 Description Of Item: Datum frame rule, steel, 202 mm x 72 mm, with parallelogram for 'boxing' the spectacle frame to determine the location of its datum with other scales engraved on the base plate to measuring eye size and locating lthe optical centres and bifocal height to be measured in relation to the datum line. Marked EMPIRE DATUM FRAME RULE / COPYRIGHT Historical Significance: This may have been made by M Wiseman and Company Ltd, a UK optical supply house. The book L S Sasieni Spectacle fitting and optical dispensing 1950 (Cat nos 776 )2243) has an informative chapter (ch 2) on frame rules and one (ch 5) on devices for face measurements. How Acquired: Donated by Bruce Dudon, spectacle maker, Woodend Date Acquired: June 2013 Condition: Very good except on pivot not secured Location: Archive office. East wall shelves unit 3. Drawer 10 |