We heard him back and turn his car and shoot away. Meanwhile, Kennedy was looking over carefully Jackson's roadster. He tapped the gas-tank in the rear, then opened it. There was not a drop of gas in it. He lifted up the hood and looked inside at the motor. Whatever he saw there, he said nothing. Finally, by siphoning some gas from Snedden's tank and making some adjustments, he seemed to have the car in a condition again for it to run. He was just about to start it when MacLeod returned, carrying a canary-bird in a cage.
"I've telephoned to town," he announced. "Some one will be here soon now. Meanwhile, an idea occurred to me, and I borrowed this bird. Let me see whether the idea is any good."
Kennedy, by this time, had started the engine. MacLeod placed the bright little songster near the stove on the work-bench and began to watch it narrowly.
More than ever up in the air over the mystery, I could only watch
Kennedy and MacLeod, each following his own lines.
It might, perhaps, have been ten minutes after MacLeod returned, and during that time he had never taken his eyes off the bird, when I began to feel a little drowsy. A word from MacLeod roused me.
"There's carbon monoxide in the air, Kennedy!" he exclaimed. "You know how this gas affects birds."
Kennedy looked over intently. The canary had begun to show evident signs of distress over something.
"It must be that this stove is defective," pursued MacLeod, picking up the poor little bird and carrying it quickly into the fresh air, where it could regain its former liveliness. Then, when he returned, he added, "There must be some defect in the stove or the draught that makes it send out the poisonous gas."
"There's some gas," agreed Kennedy. "It must have cleared away mostly, though, or we couldn't stand it ourselves."
Craig continued to look about the car and the building, in the vain hope of discovering some other clue. Had Mrs. Snedden been killed by the carbonic oxide? Was it a case of gas poisoning? Then, too, why had she been here at all? Who had shut her up? Had she been overcome first and, in a stupor, been unable to move to save herself? Above all, what had this to do with the mysterious phantom slayer that had wrecked so much of the works in less than a week?