This 1942 ad for a comptometer is just perfect because first of all, I had no idea what a comptometer was (a mechanical calculator, basically) and second, the spec sheet is wonderful: no glare dials, elimination of non-essential zeroes, and a “Keystroke Censor.”
We’ve really come quite a ways in advancing technology. The things the Comptometer was tasked to do can probably be done in 2 seconds now. Learn more about the Comptometer here. [BoingBoing]