“Or ether?” interrupted Craig. “Ether will do.”
“Oh, yes, plenty of ether.”
Craig poured a little of one of the blood samples from the jar into a tube and added a few drops of ether. A cloudy dark precipitate formed. He smiled quietly and said, half to himself, “I thought so.”
“What is it?” asked the coroner eagerly. “Nux vomica?”
Craig shook his head as he stared at the black precipitate. “You were perfectly right about the asphyxiation, Doctor,” he remarked slowly, “but wrong as to the cause. It wasn't carbon monoxide or illuminating-gas. And you, Mr. Whitney, were right about the poison, too. Only it is a poison neither of you ever heard of.”
“What is it?” we asked simultaneously.
“Let me take these samples and make some further tests. I am sure of it, but it is new to me. Wait till to-morrow night, when my chain of evidence is completed. Then you are all cordially invited to attend at my laboratory at the university. I'll ask you, Mr. Whitney, to come armed with a warrant for John or Jane Doe. Please see that the Wainwrights, particularly Marian, are present. You can tell Inspector O'Connor that Mr. Vanderdyke and Mrs. Ralston are required as material witnesses—anything so long as you are sure that these five persons are present. Good night, gentlemen.”
We rode back to the city in silence, but as we neared the station, Kennedy remarked: “You see, Walter, these people are like the newspapers. They are floundering around in a sea of unrelated facts. There is more than they think back of this crime. I've been revolving in my mind how it will be possible to get some inkling about this concession of Vanderdyke's, the mining claim of Mrs. Ralston, and the exact itinerary of the Wainwright trip in the Far East. Do you think you can get that information for me? I think it will take me all day to-morrow to isolate this poison and get things in convincing shape on that score. Meanwhile if you can see Vanderdyke and Mrs. Ralston you can help me a great deal. I am sure you will find them very interesting people.”
“I have been told that she is quite a female high financier,” I replied, tacitly accepting Craig's commission. “Her story is that her claim is situated near the mine of a group of powerful American capitalists, who are opposed to having any competition, and on the strength of that story she has been raking in the money right and left. I don't know Vanderdyke, never heard of him before, but no doubt he has some equally interesting game.”
“Don't let them think you connect them with the case, however,” cautioned Craig.