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Frederick Post Co. 1452 Universal

• Type: Closed Body Enhanced Mannheim
• Size: 10 Inches
• Material: Bamboo and celluloid
• Scales:
  • Front: Inches / A [ B CI C ] D K | Centimeters
  • Back: [ S L T ]
• HvH: 3765

This is the full sized version of the 1441 This was marketed as a sort of "everyman" rule, for nonengineers (including housewives!). Celluloid insert on reverse includes decimal fractions, circular relations, unit conversions and materials data. (And why would a housewife need to know the density of cast iron? Would it be to calculate the dent she's going to put in her carousing husband's head with a frying pan?)

This seems to be the same rule as others marked 1452W. 3/32-inch hole in upper left, probably not original.

Dated July 1971 ("VG" mark on reverse)