of the story
which had been published so far. But there were many other details of
the poisoning he was quite willing to discuss frankly.

"It was true about the jar of ammonia?" asked Kennedy.

"Yes," he answered. "It was standing on her dressing-table with the
note crumpled up in it, just as the papers said."

"And you have no idea why it was there?"

"I didn't say that. I can guess. Fumes of ammonia are one of the
antidotes for poisoning of that kind."

"But Vera Lytton could hardly have known that," objected Kennedy.

"No, of course not. But she probably did know that ammonia is good
for just that sort of faintness which she must have experienced after
taking the powder. Perhaps she thought of sal volatile, I don't know.
But most people know that ammonia in some form is good for faintness
of this sort, even if they don't know anything about cyanides and--"

"Then it was cyanide?" interrupted Craig.

"Yes," he replied slowly. It was evident that he was suffering great
physical and nervous anguish as the result of his too intimate
acquaintance with the poisons in question. "I will tell you precisely
how is was, Professor Kennedy. When I was called in to see Miss Lytton
I found her on the bed. I pried open her jaws and smelled the sweetish
odor of the cyanogen gas. I knew then what she had taken, and at the
moment she was dead. In the next room I heard some one moaning. The
maid said that it was Mrs. Boncour, and that she was deathly sick.
I ran into her room, and though she was beside herself with pain I
managed to control her, though she struggled desperately against me. I
was rushing her to the bathroom, passing through Miss Lytton's room.
'What's wrong?' I asked as I carried her along. 'I took some of that,'
she replied, pointing to the bottle, on the dressing-table.

"I put a small quantity of its crystal contents on my tongue. Then
I realized the most tragic truth of my life. I had taken one of the
deadliest poisons in the world. The odor of the released gas of
cyanogen was strong. But more than that, the metallic taste and the
horrible burning sensation told of the presence of some form of
mercury, too. In that terrible moment my brain worked with the
incredible swiftness of light. In a flash I knew that if I added malic
acid to the mercury--perchloride of mercury or corrosive sublimate--I
would have calomel or subchloride of mercury, the only thing that
would switch the poison out of my system and Mr