hich really affected her?
and was her apparent indifference at meeting him only an evidence of her
self-control? It seems an impossible conclusion to draw, and indeed
there are nothing but hitches and improbable features in this case.
Nothing fits; nothing jibes. I get just so far in it and then I run up
against a wall. Either there is a superhuman power of duplicity in the
persons who contrived this murder or we are on the wrong tack
altogether."

"In other words, you have tried every means known to you to get at the
truth of this matter, and failed."

"I have, sir; sorry as I may be to acknowledge it."

"Then we must accept her terms. She can be shadowed?"

"Every moment."

"Very well, then. Extreme cases must be met by extreme measures. We will
let her have her swing, and see what comes of it. Revenge is a great
weapon in the hands of a determined woman, and from her look I think she
will make the most of it."

And returning to where the young girl stood, the Superintendent asked
her whether she felt sure the murderer would not escape in the time that
must elapse before his apprehension.

Instantly her cheek, which had looked as if it could never show color
again, flushed a deep and painful scarlet, and she cried vehemently:

"If any hint of what is here passing should reach him I should be
powerless to prevent his flight. Swear, then, that my very existence
shall be kept a secret between you two, or I will do nothing towards his
apprehension,--no, not even to save the innocent."

"We will not swear, but we will promise," returned the Superintendent.
"And now, when may we expect to hear from you again?"

"Two weeks from to-night as the clock strikes eight. Be wherever I may
chance to be at that hour, and see on whose arm I lay my hand. It will
be that of the man who killed Mrs. Van Burnam."

XXXVIII.

A WHITE SATIN GOWN.

The events just related did not come to my knowledge for some days after
they occurred, but I have recorded them at this time that I might in
some way prepare you for an interview which shortly after took place
between myself and Mr. Gryce.

I had not seen him since our rather unsatisfactory parting in front of
Miss Althorpe's house, and the suspense which I had endured in the
interim made my greeting unnecessarily warm. But he took it all very
naturally.

"You are glad to see me," said he; "been wondering what has become of
Miss Oliver. Well, she is in good hands; with M