Circular slide rule with lockable cursor arm

Made:
California

Circular slide rule with lockable cursor arm, plastic, in envelope with instructions: " Eckel dial rule", Engineers' Model, made by Lithocalculator Company, Calfornia

Details

Category:
Mathematics
Object Number:
1985-276
type:
circular slide rule
credit:
Crosby, R.C.

Parts

Circular slide rule with lockable cursor arm

Circular slide rule with lockable cursor arm

Object Number:
1985-276 Pt2
type:
circular slide rule