morning. I think
Miss Thurston already understands my escapade. I have taken her into my
confidence."

Mrs. Wilson directed at Barbara a glance so compelling that it was
almost hypnotic.

Bab did not return her look or make any answer.

A little while later Barbara disappeared. She went back alone to Mr.
Hamlin's study. On top of his desk she discovered a box about a foot and
a half long. It had been opened and a key was lying beside it on the
desk. Barbara could see that there was no money in the box, only a
collection of papers. Bab returned the long envelope, which she had found
at Mrs. Wilson's feet in the hall to its place, turned the key in the
lock of the box, and then carried the key upstairs, intending to hand it
over to Harriet. But Bab did not know whether or not she ought to explain
to Harriet how she had come by the key.

Harriet was in the room with Mrs. Wilson, seeing her guest to bed for the
second time, when Barbara went upstairs. Bab had no desire to face Mrs.
Wilson again that night. The distrust of the woman that was deepening in
the girl's mind was too great to conceal.

"Come into my room in the morning before breakfast, Harriet, dear," Mrs.
Wilson entreated, as she kissed her young hostess good night. "I know you
will forgive my foolishness, when I have had a little talk with you. It
is too late now for explanations."

It was between two and three o'clock in the morning before the household
of the Assistant Secretary of State again settled itself to sleep. Under
her pillow Barbara Thurston had the key to Mr. William Hamlin's strong
box, in which valuable state papers were sometimes temporarily placed.

CHAPTER XVIII

A TANGLED WEB OF CIRCUMSTANCE

Harriet Hamlin spent half an hour in the room with Mrs. Wilson before she
came down to the breakfast table the next morning.

"It is all right, girls," she announced promptly, as soon as the maid
left the room. "Mrs. Wilson is going to have her breakfast in bed. She is
a little upset by the happenings of last night. But she has explained
everything to me. For some time, Mrs. Wilson has been trying to play a
joke on Father, and last night she made another attempt. I promised her
none of us would mention to him what had occurred. Will you give me your
word, all of you, not to tell?"

"Certainly, Harriet," Ruth agreed seriously. The other three "Automobile
Girls" quietly nodded their heads.

"I don't know that I quite approve of Mrs.