1. The Versalog Slide Rule Instructions,1951, 115 pages , pub Frederick Post Company £20 (Cover spine detached)
2. The Mannheim Slide Rule, complete manual, William Cox, 48 pages paper covers, 1917 (good condition) £25
3. The Slide Rule, C. N. Pickworth 20th Edition, 1935. (Reasonable condition) £20
4. Instructions for the Use of A. W. Fabers Improved Calculating Rule, by C. N. Pickworth, 14 folding sheets of scales, (Cover rough but intact) uncommon, undated probably 1910. £50
Ask the Dealer
Fletcher Wallis sells objects and books relating to the history of science, medicine and technology from his unit at Admiral Vernon Arcade Portobello Road. He publishes books through Vernier Press, including Antique Medicine Chests, and Corkscrew Patents from 1795. He has been dealing for thirty five years.