Card sharp versus card shark

[Michael Quinion]

It is sometimes said that the modern form "card shark" is a folk
etymology from "card sharp". RHHDAS has 1942 for the first appearance
of "card shark" and 1884 for "card sharp", though OED2 has 1859 for
"card sharper", which would seem to be the older form. I've found
these antedatings for "card shark":

1912 House, Edward Mandell "Philip Dru: Administrator" chapter 57
"But the astute boss has planned all that far in advance, the
candidates are selected and the platform written and both are
'forced' upon the unsuspecting delegate, much as the card shark
forced his cards upon his victim."

1921 Stratton-Porter, Gene "Her Father's Daughter", Chapter 19 "They
were a prize given by a bridge club at an 'Ambassador' benefit for
the Good Samaritan Hospital. Eileen, the little card shark she is,
won it, and she was keeping it hidden away there to use as a gift for
my birthday."

In view of what is now a relatively small gap between the dates of
appearance of the two forms, could it be that they derive from
distinct sources and ran more in parallel than in opposition? Or is
it that "sharp" and sharp" are the folk etymological pair, from much
further back? The OED also notes that "shark" and "sharker" were
derogatory slang terms in related senses, including that of cheaters
at cards, during the seventeenth century.

I'd very much welcome comments.

--
Michael Quinion
Editor, World Wide Words
E-mail: <TheEditor at worldwidewords.org>
Web: <http://www.worldwidewords.org/>