Rabdologiae seu Numerationis per Virgulas libri duo: Cum Appendice de expeditissimo Multiplicationis promptuario. Quibus accessit & Arithmeticae Localis Liber unus. John NAPIER.

Rabdologiae seu Numerationis per Virgulas libri duo: Cum Appendice de expeditissimo Multiplicationis promptuario. Quibus accessit & Arithmeticae Localis Liber unus.

Nine folding tables (woodcut & letterpress), & numerous woodcut diagrams & tables in the text. 6 p.l., 139 pp., 2 blank leaves. 12mo, cont. mottled calf (very slightly rubbed), panelled in gilt. Leyden: P. Rammasen, 1628.

Third edition; this edition is much rarer than the first edition of 1617. This is the first description of a calculating machine.

"In 1617 Napier's intense concern for the practicalities of computation led him to publish another book, the Rabdologiae, which contains a number of elementary calculating devices, including the rods known as 'Napier's bones.' These rods, which in essence constitute a mechanical multiplication table, had a considerable vogue for many years after his death."-D.S.B., IX, p. 610-(& see the rest of the article for more details).

Nice crisp copy.

Dibner 107-(1st ed.). See Printing & the Mind of Man 116-(in this work Napier "announced another important invention, 'Napier's Bones'...They were the precursors of seventeenth-century and modern calculating machines and computers."

Price: $12,500.00

Item ID: 62