3-in-One Oil is (still) OK for Guns by Kirk Lawson [1915 advertisement from Arms & The Man] Invented in 1894 by George W. Cole, ostensibly as a bicycle chain lubricant, 3-in-One is the original "CLP" oil. The "3" part of 3-in-One actually stands for "Clean, Lubricate, and Protect." By at...