Cincinnati, OH: American Fluresit Company, nd, c. 1950. Original edition. Advertising wooden ruler. Wooden ruler with black lettering. There are four scales on this ruler. On the front of the rule, the first scale measures inches, but numbers it so that 1 inch = 4 feet. The other scale measures joists 16" on centers, with each tick mark being about 5/16" apart. The two scales on the back of the ruler double the scale so that 1 inch = 8 feet. Very Good. Item #20688
The front of this ruler celebrated the development of lapidensin, a colorless liquid which waterproofed and dampproofed exterior masonry walls above grade, including brick, stone, and stucco. The back side of the ruler advertised their floor hardeners, such as Duromit, Durocrete, and Dust-A-Lay. An interesting, collectible advertising piece.