From Wiki

Keuffel and Esser Model N9081-3 "Doric" Log Log Duplex Decitrig

• Type: Log Log Duplex
• Size: 10 Inches / 25 cm
• Material: Mahogany and celluloid
• Scales:
  • Front: LL02 LL03 DF [ CF CIF CI C ] D LL3 LL2
  • Back: LL01 K A [ B T ST S ] D L LL1
• HvH: 4241

Identical in function to the N4081-3. Made with "Xylonite", a material that wasn't used long due to brittleness. The current unit has a chip in the slide, seen at the right-hand end.

Serial number 52147 suggests a manufacture date in 1954.