Multiplication.
Its Simplicity as done on the Comptometer illustrated by diagram.
Copyright 1894, by Felt & Tarrant Mfg. Co.
RULE.—Begin at the right of the rows of keys indicated by the first figure of the multiplier, and strike each successive key in the same row towards the left as many times as indicated by the corresponding figure in the multiplicand. Proceed with each figure of the multiplier as with the first, beginning always in the column of keys in which the figure of the multiplier stands.
Explanation of Diagram.
See black lines descending from arrows on cut. Each line represents a stroke on the key in performing the following example: Example 2253×84. Because 4 is the first figure of the multiplier, begin on the first key of the row of 4s and strike the first one three times, the second one five times, the third one two times and the fourth one two times—that is, strike each key in succession the number of times indicated by the corresponding figure of the multiplicand (2253).
8 being the second figure of the multiplier, begin on the second key in the row of 8s and strike three times, move to the next key to the left and strike five times, etc., etc., when the answer, 189252, is shown on the register in front. (See cut.)
Observe that in multiplying the finger only moves from one key to its next neighbor, therefore keep the eyes on the paper, not on the keys. (See finger exercises on page 5 and proper position of hands on page 8.)
