Reckoning Apparatus for Multiplication by a Simpler Method, Multiplying-reckoning-tables and Result-finding-slip.

摘要

18,538. Bremer, H. Aug. 27. Calculating-apparatus.-An apparatus for facilitating multiplication consists of a frame on which slips bearing numbers from a multiplication table are arranged, and the vertical rows then added as in arithmetic. In multiplying 782 by 39,841 the numbered strips C, Fig. 1, corresponding to the multiplier are arranged for the units, tens, hundreds, and other rows in the frame B, B1 on the board A, and upon them are written the proper three-by-one-figure products from the table, Fig. 2. Addition then gives the product. For obtaining four-by-one-figure products a slip, Fig. 3, is applied to the table of products, with the arguments on its top line upon the proper columns of the table. A row of figures is seen through a slit, and below them appear an integral thousand number at the left, followed by the products of itself and the first nine numbers. Thus the sum of the two numbers under " 6 " is six times the sum of the two numbers on the extreme left. There is a separate slip for each integral thousand.