Posted by Bruce Kahl on April 08, 2001
In Reply to: The Real McCoy posted by Tom Herren on April 07, 2001
: As a retiree from UNOCAL Science and Technology in Brea California, I worked in the Products Research Section, in paricular Technical Services. My understanding of the origin of "the Real McCoy", without documentation, is that it was an ex-slave named McCoy that had developed an oil for lubricating steam engines before the intoduction of automatic lubericators. The engineer had to stop every once in awhile and manually lubricated the pistons and associated machinery with lubricating oil. McCoy's apparently contained animal fat or lanolin to help the oil stick to the wet working parts. As you know, water and oil do not mix very well. Of course the engineer wanted to make shure he had the "real McCoy" oil that worked better that just plain oil. Steam Cylinder oils are still in use today.
From World Wide Words:
"There are at least half a dozen theories about which of the myriad McCoys of America at the end of the nineteenth century is the genuinely real McCoy. Was it, as Alistair Cooke argued, a famous cattle baron? Or was it perhaps Elijah McCoy, who invented a machine to lubricate the moving parts of a railway locomotive? The broad consensus seems to be that it was Kid McCoy, the former welterweight boxing champion of the 1890s. He had so many imitators, taking his name in boxing booths in small towns throughout the country, that it seems he had eventually to bill himself as Kid "The Real" McCoy, and the phrase stuck.
The Oxford English Dictionary records this from a letter written by the author Robert Louis Stevenson in 1883: "He's the real Mackay". It's not only in a different spelling, but a decade before Kid McCoy became famous, and almost certainly refers to the famous Scottish firm of whisky makers."