The Mergenthaler Linotype. The reason nearly all materials (books, newspapers, magazines) printed up until the 70's were produced in columns about 3.66" wide.

Gutenberg invented moveable type, Ottmar Mergenthaler invented the machine that could cast the type fast enough to print a daily paper.

My first job out of college was for a check printing company still printing at 42 plants with Linotypes until the late 80's when we converted to offset lithography.

From 1889 to 1989 quite a few of us had type metal in our veins...literally.