Mary Leah --

OCLC WorldCat database lists about a 100 entries for George Gregory Smith
as an author and editor.  His dates are given as 1865-1932.  Most of his
works were published under imprints of publishers based in London and many
entries are for the publication "Spectator."  _Mark Twain's Library: A
Reconstruction_ indicates that Twain did read "Spectator."

One entry is an auction catalog for the sale of the library of the late
Prof. G. Gregory Smith on July 27th, 1932.

None of these preliminary entries are positive evidence that he is
"Twain's" George Gregory Smith, but his dates and his background seem to
make him a likely suspect who might merit further investigation.

Barb