Posted 9 years ago
Hughoneill
(1 item)
Keuffel and Esser slide rule. Young's Specific Gravity & Compound Cost Calculator. Copyrighted 1913.
The main centre slide is reversible, one side measures gravities and the other measures percentages. It's made of timber and, either, bakelite or formica. It still has it's original tan leather case.
I know it was used by someone working for the Firestone tyre company.
If anyone has further information I would be interested discovering more about this piece.
