Slide rules
In message , Bob Eager
writes
On Mon, 09 Dec 2019 15:22:23 -0800, petek wrote:
Thornton P201. Two sided with 3 "Log Log" scales (LL1, LL2 and LL3)
which I never did find a use for. Still has a silky smoooth action. Talk
Ah. It seems that mine has: LL1-3, LL1-3 reciprocal, Reciprocal C and D,
Pi-displaced C and D (conventional multiplication), cube roots,
logarithms, orthodox trigonometric, vector analysis ...
Bloody clever these things were!
Just dug out of the drawer.. mine is an Aristo scholar with more scales
than I ever found useful. Because it does not have a solid spine,
gripping the sides locks the slider which, once you have practiced,
avoids movement errors.
--
Tim Lamb
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