Mathematics Antique - Smith and Dolier Arithmetical scales. Simple Subtraction

circa1830/1842. Complete.

An ingenious set of boxwood rods designed to teach Subtraction. With instructions printed on the underside of the hinged lid. By rotating the sticks, various tasks can be calculated and the correct result can then read on another rod. See photographs illustrating.

Designed for the use of schools (group work up to 4 students) and private families. Produced by Egerton Smith (1774-1841) and William Dolier (1790-1869). Sold by J. Phelps, London; Thomas Taylor, Liverpool;  Wrightson and Webb, Birmingham; and all booksellers.

These are a rare surviving example of a Georgian mathematical teaching aid. Similar sets are held in the collections of The Science Museum, London.

Complete and in very good condition although almost 200 years old.

Dimensions 32cm x 12.3cm x 2.2cm;
Weight:  approx. 400 gm.