PALMER'S POCKET SCALE, WITH RULES FOR ITS USE IN SOLVING ARITHMETICAL AND GEOMETRICAL PROBLEMS. ROCHESTER: PUBLISHED BY AARON PALMER. 1845. PALMER'S ENDLESS SELF-COMPUTING SCALE. THE proprietors of this invaluable work, beg leave to present the public with the following notice: This Scale (the result of three years' incessant labor) is designed as an assistant in all arithmetical calculations. The simplicity, rapidity, and accuracy of its results have astonished our best mathematicians. It consists of a logarithmic combination of numbers, arranged in two or more circles, one of which is made to revolve within the other; which process constantly changes the relation of the figures to each other, and solves an infinite variety of problems. Its advantages are 1st. A complete saving of mental labor; for, by the use of this Scale, the most intricate calculations are but a pleasurable exercise of the mind. 2d. A great saving of time. Computations requiring from three to four days, are wrought out by this Scale in the incredible short space of one minute. 3d. Complete accuracy. The results of the computations on this Scale are infallible. Errors are entirely out of the question, except through sheer carelessness. 4th. Mental improvement. By this Scale, a knowledge of the philosophy of numbers, and their relation to each other, is soon obtained. So that, in a little time, many of the common calculations are wrought out by the mere exercise of the mind |