like?"

"It was blue at first but on contact with the air quickly changed to
brownish-white and lost itself, it was so fine."

"Evaporated?"

"You can call it that if you wish. It was intense. I held it at arms'
length, yet it made me sick and I had cramps for over an hour
afterwards."

"It would have killed you if you had placed it to your mouth or nose?"

"Not the slightest doubt of it."

"May I ask where you got the stuff?"

"It was imported into this country by a drug firm merely as a
curiosity. They put it up in tiny vials which I suppose were sent
around to different persons like myself. It was a dangerous piece of
business and I gave them no credit for doing it."

"What was the name of the firm?"

"I would not tell everybody, but I know I can trust you to keep a
secret. The firm was Alexander & Company, of Rochester, who stand very
high in the trade. I buy many things from them, from time to time, and
their traveling man, a Mr. Ostrello, gave me the powder when he called.
He told me how the firm had experimented on a dog and an ox. Both died
in less than two minutes, and each with cramps. But after death
neither animal showed the least trace of the poison."

"Wasn't this Ostrello afraid to handle the stuff?"

"Not as much as I was. He said he was a bit used to it. I told him I
didn't want to get used to it. Have another glass of wine?"

"No, I prefer to smoke, thanks just the same. I am interested in this
_yamlang_, as you call it. Where can I get the stuff?"

"No more of it can be had. I rather think they got afraid of it.
Wait, I'll get the vial it was in. Perhaps there is a whiff left in
it."

"Thanks, but do you think I want to die?" queried the detective, and
gave a laugh.

When the empty vial was produced he opened it and took a short sniff.
Then he drew his breath in sharply. A faint odor was perceptible, the
same odor he had detected in the carpet on the upper hallway of the
Langmore mansion.

"Do you smell it?" questioned the physician.

"Yes, but not very well. I don't think it will affect me much."

"I trust not, my dear Adams. We cannot afford to lose you. Now, what
is it all about?"

"Another case, that's all. I don't feel like talking about it just
yet. I'll give you the particulars some other time."

"And have I helped you?"

"I think you have."

"Of course there are other powders--and there is chloroform--"

"I think we have struck a clue in this