Herbert Bayer, universal alphabet, 1925. This experiment in reducing the alphabet to one set of geometrically constructed characters has differences between letterforms maximized for greater legibility. The lower forms show different weights. Later, Bayer developed variations such as the condensed bold, typewriter, and handwriting style shown here. The Museum of Modern Art, N.Y.

source
1.A History of Graphic Design
2.http://linneamotts.blogspot.com/2010/01/herbert-bayer-universal-typeface.html