SUN HEMMI
POCKET SLIDE RULE
No. 135
Made in Japan
in leather case
Approx. 6" long
Mitsubishi Heavy Industries Ltd and logo on the back
A slide rule is a hand-operated mechanical calculator
consisting of slidable rulers for evaluating mathematical operations
such as multiplication, division, exponents, roots, logarithms, and
trigonometry. It is one of the simplest analog computers