Cover title.
Contents: United Kingdom patent system and selected slide rule patents from 1735 to 1920 / John V. Knott - Check figures: a once ubiquitous tool for book-keepers / by Bruce O.B. Williams.
Slide rule and calculation monographs. ISBN 0953503933. Published by Colin Barnes in conjunction with the U.K. Slide Rule Circle in 2002. Publication and catalogue information, links to buy online and reader comments.