Treasure Trove

I'm not sure what started me thinking about slide rules this afternoon, but once I did, I wondered if they are still available.

Manufacture seems to have stopped in the 1970's, but second hand rules are still available, in fact they are collectors' items, with prices ranging from just over $100 for a simple rule to more than $300 for a rule with lots of scales.

I suspect that my 24 scale Thornton's two sided rule, with vector scales and differential trig scales is quite a treasure.