Diagram of Linotype matrix teeth. In the drawing on the left, the matrix is about to drop because the only teeth on the rail (shown in black) correspond to tooth positions that are cut away on the matrix. The teeth present on the matrix, with the most significant in the bottom of the V, encode the binary number 0001101, decimal 13. This means that it would fall into channel 13−2 = 11 of the main magazine, the letter ‘l’.
The drawing in the middle shows a matrix with all teeth present — a pi matrix.
Date
Source
Linotype Machine Principles, published by Mergenthaler Linotype Company, Brooklyn, NY, 1940, p. 270
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