Sama and Etani reference tables and circular slide rule

Sama & Etani Vintage Professional Concise Science Tables and Circular Slide Rule

VTG 1960 Monsanto CTCS-552 Concise Science Tables & Circular Slide Rule

Vintage Concise Circular Slide Rule and Conversion Tables CTCS-552, Sama & Etani

VTG 1969 Sama & Etani Concise Science Tables & Circular Slide Rule U.S. Gov’t

Circa 1970, Concise Conversion Tables and Circular Slide Rule. Model EE-112.

Vintage Monsanto Chemical Concise Conversion Tables & Circular Slide Rule Flaws

Vintage Concise Circular Slide Rule Case Simmons Precision Nash Controls