There is excellent material on this subject on the WWW. See Plumbing and
Mechanical Magazine for July 1994 - <The Men Who Made the Water
Closet>

Also see On line Science and Technology for <Thomas Crapper---Fact or
Fiction> (I am sorry to report that the fine biography of Sir Thomas,
<Flushed with Pride> seems to have been a hoax or at least , very sloppy
scholarship.)