According to David Levy's biography, "Howard Staunton", Edgar Sheppard acted
as second for Staunton in the negotiations for a second match against Daniel
Harrwitz, to whom he sent a letter, dated 6 January 1854, demanding the
forfeited 25 pounds.

I would like to know whether Edgar Sheppard was a chess player, please.

He was a fairly distinguished doctor specialising in psychology, and for
some time he worked at Colney Hatch. Sheppard's wife was Belgian, and
while the said negotiations were in progress, Staunton spent some time in
Brussels, which is probably a coincidence, but could indicate an unsuspected
relationship between the two men - perhaps even doctor/patient, but that
is, of course, highly speculative. As you may know, Staunton played against
Lasa while he was abroad. Was that the main purpose of his visit, or did it
arise from the opportunity of his already being in Brussels?

Later, in 1864, Staunton himself wrote a letter from "Colney Hatch Park",
which again is probably a coincidence and nothing to do with Sheppard.

Best wishes,

John Townsend
Howard Staunton research project:
http://www.johntownsend.demon.co.uk/page7.html