12mo. vi, 4, 194pp. Contemporary calf boards, recently rebacked. Boards worn and marked. Book-label of Erwin Tomash to FEP, leaves browned and damp-stained, occasional ink-spots.

Thomas Dilworth (d.1780), Anglican clergyman and schoolmaster at Wapping. His Schoolmaster's Assistant was a guide to basic arithmetic designed for the instruction of children. As with his earlier manual of English instruction and spelling, A New Guide to the English Tongue, it secured commercial success in both the British Isles and in North America - several exercises from this present work are found in the school notebooks of Abraham Lincoln. As is often the case with these early schoolbooks, institutional holdings of the numerous individual editions are limited.

From the recently dispersed library of Erwin Tomash (1921-2012), American engineer recognised for his early pioneering work with computer equipment peripherals. His library consisted of over 3,000 books and manuscripts relevant to the history of computation, from medieval and renaissance works on arithmetic, finger-reckoning and the abacus, to the birth in the twentieth century of theoretical and practical computer science under Alan Turing.