The collection of papers and books of the late Dr. F. W. Lanchester, F.R.S., held in the library of the Lanchester College of Technology, Coventry, contains a paper cover booklet entitled Lanchester’s “Potted Logs”, Parts I and II, printed and published by Taylor and Francis Ltd., Red Lion Court, Fleet Street, E.C.4, in 1939, priced 2s. The booklet measures 4ξ × 7¼ and consists of 27 pages devoted to “a concise tabulation (slide rule auxiliary)” of common and natural logarithms for engineers. In Part I (14 pages) “a new system is disclosed by which the Logarithms of Numbers running to seven or eight figures may be evaluated to seven places of decimals and vice versa” Of these 14 pages, 5 only are required for the tables, the remainder being devoted to preface, introduction and worked examples. In Part II (8 pages, 4 of which are tables) the system is extended to cover natural logarithms. The remaining pages contain a note on the musical scale (“of interest to the musician, it is a table in antilog form to the base 1-059463 . . and is the foundation of the system of equal temperament”) and lists of papers, lectures, reprints, reports, memoranda and books by Lanchester.