chapter ix., “ De numeris Pythagoricis.” A curious illus-

tration occupies one page, “ Numerorum Descriptio,” stating that “ Asinus significabit ciphram, quia (ut dicunt) Asinus nihil valet ” ; he illustrates the other numerals, thus : — 1j a pestle and a spear ; 2, a fork, a pair of scissors ; 3, a three- legged stool and an open tripod ; 4, a “ pileus quadratus,” a book ; 5, a trumpet, a gourd ; 6, a chemical retort, a snail ; 7, an axe, a square ; 8, a pair of spectacles, also “ nates ” (!) ; 9, a curled up serpent, a dog’s tail ; 10, a spear pointing to the head of an ass.
The fourth book treats of Geometry, in all its differing figures. The fifth book treats of Military Arithmetic ; the sixth, of Musical Arithmetic ; the next, of the Arithmetic of Astronomy and Astrology ; the ninth, “ De Arithmetica Pythagorica.” It has two curious specula. The tenth book treats of Mental Arithmetic ; and the last, “ De Arithmetica Jacosa.” It is remarkably short, the whole