MI Printing: History of Typesetting Linotype Machine

The invention of a machine to replace the labor-intensive task of setting type by hand was one that many inventors had tackled during the 19th Century. The Mergenthaler Linotype Company is a corporation founded in the United States in 1886 to market the linecaster invented by Ottmar Mergenthaler. The difficulty was not in creating the text, but in returning the characters to a proper position for future use. Mergenthaler solved this problem by placing type molds on the sides of specially keyed matrices. The matrices would be lined up and hot lead alloy forced to fill the matrices, creating the line of type. Then the matrices would progress through the machine, where a special keying system on one end of the matrix, unique for each character, would allow the matrix to drop only into the correct storage slot, ready for future use.

Another problem Mergenthaler solved was in justifying the type, giving flush margins on the left and right. Hand compositors did this by using spaces of different widths in a line, to ensure that the lines all ended at the same point. Mergenthaler adapted the "space band" (patented by J. W. Schuckers), a device consisting of two wedges of metal connected loosely. When a line of type was being justified, all the space band wedges would be pushed up in two passes to spread the line out to the full measure being cast. The space bands were stored for reuse in a different location from the matrices.