Slide rules

Alro El A

AL-RO was a company founded in the 1930 by Ir C.J. Dussel & A. Pasveer. Their uniqueness of the circular slide rules was the metal case, which not only protected the metal case, but also acted as a stand for desktop use. At the end of the 1950s the company stopped producing the circular slide rules.

The Oughtred  Society made a special article about these circular slide rules in 2006.

The Alro El A has turnable scales and was used for car technics caculations for motor dynamo Amp KW etc.  The diameter is 13cm. The metal is aluminium.

This item  is in a very good condition.

If you want pictures in a better resolution, don't hesitate to email me