_Unknown_ (Flemish School; 15th-16th century).
_See also_ (p. xx)
"In Flemish pictures the varnish was incorporated with the surface
colours, and cannot be removed without destroying at the same time
the very fabric of the work. For this reason all attempts to, what is
called, _restore_, or clean pictures of the Flemish School, result only
in the destruction of the work, and by this means many fine pictures
have, for all practical purposes, perished.... (This picture) is a
lamentable example" (Conway's _Early Flemish Artists_, p. 119).