My collection was not intended to be a large one but I at first aimed to obtain a representative selection of slide rules from around the world. If I have a preference for anything then it is early slide rules, British slide rules (especially Blundell Rules Ltd and Blundell Harling) and the unusual, where finance permits.
I started with my slide rule from my student and work days - a well used Thornton P271, and also an early alcohol rule, which I inherited. Initially I just collected what I was offered, apart from a few, early, boxwood rules bought at antiques fairs before they started getting too expensive. However, since I started buying on e-Bay, my collection has grown significantly and, at the present time, comprises over five hundred items. I now concentrate on British slide rules
In the pages which follow, I have divided the collection by maker or country of origin, except for the first page which covers my early rules and the last two which contain slide charts and exposure calculators.
Joint Slide Rules by Peter M Hopp C.eng. MBCS
This recently published book of over two hundred pages and more than 100 colour illustrations covers all sorts of jointed calculating rule in detail and is a thoroughly recommended ‘must have’ for all collectors of these interesting, early slide rules of which, perhaps, the best known is the carpenter’s or Coggeshall rule.
It is available direct from the publishers, Jeremy Mills Publishing Ltd., 112 Lidget Street, Lindley, Huddersfield, W Yorks, HD3 3JR.