slight,
although it may be, it is--"

[Illustration: "I have a clue."]

She drew from her pocket a small white roll, and unfolding it, held up
for his inspection _half_ of a fine cambric handkerchief, and a tiny
stoppered vial of finest cut glass.

Doctor Heath glanced at the vial and uttered one word.

"Chloroform."

"Chloroform," repeated Miss Wardour; "when I was awakened, by the
knocking at my door, I found this," shaking the fragment of cambric,
"lying lightly across my face; and the vial, on the little night stand
beside my bed. Aunt Honor was rapping for admittance, and when she had
made me comprehend the situation, we decided that it was best to say
nothing of this. What seems most strange is, that it was administered
with so much care; I am affected by the smallest quantity of the drug,
and an ordinary dose would have put me under medical treatment. I could
not have left my bed for a week, had they given me as much as would
serve only to stupify Aunt Honor there."

"No," interrupted Mrs. Aliston, once more half emerging from her window.
"It would have been worse than that; I think an overdose of chloroform
would kill Constance. It seems as if they knew just how much to give."

Was it fancy, or did a troubled look rest for a moment in the eyes of
Doctor Heath, and on his countenance a shade of pallor?

"This is, to my mind, the most serious aspect of the affair," he said
gravely. "Mrs. Aliston is right; an overdose of that drug would be fatal
to you. Your life has been jeopardized. I agree with Mrs. Aliston, your
investigation _is_ in the hands of bunglers; let us hunt these fellows
down."

"I will see that an officer is telegraphed for at once; but--shall I
send to the regular bureau, or--how?"

"There is one man in the city, if he _is_ in the city now, who is
qualified for the position he holds. He has withdrawn himself from the
regular force, and acts solely on his own responsibility. He is much
sought after, and possesses wonderful abilities; some of his exploits
have been truly astounding."

"And this man is--"

"Mr. Lamotte; Mr. Francis Lamotte," announced a servant.

"Show them in," said Constance, at the same time gathering up the piece
of cambric and the little vial and putting them in her pocket.

Doctor Heath arose, and taking up his hat, murmured an apology.

"I have a patient at this hour, Miss Wardour, and will call again during
the day. You will not stand in need of my counsel