Rock-A-By Razor (Apr, 1948)
This nonelectric razor gives you a dry shave when you hold it against the skin and rock it gently back and forth. Its two blades, explains the British manufacturer, cut the whiskers by a scissors movement. At the same time the guard sharpens the blades, and is said to give them a life of several years. The blades, moving in a half circle, crop the beard bristles that project through the perforated guard shown above.