The colloquies with the class were spirited, sarcastic, interesting.
Here is a characteristic one:

_Question:_ "Do you know what I mean when I say tone, value, light,
shade, quality, movement, construction, etc.?"

_Chorus:_ "Oh, yes, Mr. Whistler!"

_Mr. Whistler:_ "I'm glad, for it's more than I do myself!"

* * * * *

He objected to smoking in the atelier, partly because it obscured the
light and partly because of its obfuscating qualities. In Paris a big
Englishman clouded the class-room with a copious discharge of smoke.
"My dear sir," said Whistler, gently, "I know you do not smoke to show
disrespect for my request that students refrain from smoking on the
days I come to them, nor would you desire to infringe upon the rules
of the atelier, but--er--it seems to me--er--that when you are
painting--er--you might possibly become so absorbed in your work as
to--er--let your cigar go out!"

Visiting Earl Stetson Crawford in his studio at Paris, he noted on the
wall a photographic copy of the Nicholson portrait of himself.

"Is that the best you have of me?" he asked. "Not that it is not very
beautiful and artistic and so on--but I say, come now, you don't think
it quite does me justice, do you?"