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Frederick Post Co. 1460 Versalog and Versalog II

• Type: Log Log Duplex
• Size: 10 Inches
• Material: Bamboo and celluloid
• Scales:
  • Versalog Front: LL0 LL/0 K DF [ CF CIF CI C ] D R1 R2 L
  • Versalog Back: LL/1 LL/2 LL/3 [ T ST S C ] D LL3 LL2 LL1
  • Versalog II Front: LL/0 K A DF [ CF CIF CI C ] D R1 R2 LL0
  • Versalog II Back: L LL/1 LL/2 LL/3 [ T ST S C ] D LL3 LL2 LL1
• HvH: Versalog: 2217; Versalog II: 3783

Log-log rule with decimal trig and 2-line square root scale. ST scale marked "SRT" on Versalog II ; markings on rule for trig cofunctions. Older Versalog has manufacturer data on the top edge of the rule, above the LL0 scale. Versalog II has a more symmetric arrangement of scales, and manages to make room for the A scale that users seemed to miss. (But, imagine: Use the A scale against the R1 and R2 scales to get fourth powers for free!)

Both rules with leather cases. Made in Japan by Hemmi.

Versalog II Engraved on frame with "KA-SS-EP-L48505". Readers are invited to amplify.

Original Versalog dated April 1955 ("FD" mark on upper edge)

Versalog II dated July 1970 ("UG" mark on lower edge)