"Oh, yes, always on business, but--well, madame, she was a very
beautiful woman. Perhaps he like beautiful women--_eh bien?_ That was
before the Doctor Gregory treated madame. After the doctor treated
madame M'sieur Lawrence do not call so often. That's all."

"Are you thoroughly devoted to Mrs. Close? Would you do a favor for
her?" asked Craig pointblank.

"Sir, I would give my life, almost, for madame. She was always so good
to me."

"I don't ask you to give your life for her, Marie," said Craig, "but
you can do her a great service, a very great service."

"I will do it."

"To-night," said Craig. "I want you to sleep in Mrs. Close's room. You
can do so, for I know that Mr. Close is living at the St. Francis Club
until his wife returns from the sanitarium. To-morrow morning come to
my laboratory"--Craig handed her his card--"and I will tell you what
to do next. By the way, don't say anything to anyone in the house
about it, and keep a sharp watch on the actions of any of the servants
who may go into Mrs. Close's room."

"Well," said Craig, "there is nothing more to be done immediately." We
had once more regained the street and were walking up-town. We walked
in silence for several blocks.

"Yes," mused Craig, "there is something you can do, after all, Walter.
I would like you to look up Gregory and Close and Lawrence. I already