Kennedy turned to him. Something in the tone of his voice showed that he meant his compliment. "I'm glad, Mackay, to be called in by some one who knows enough not to destroy evidence; who realizes that perhaps the slightest disarrangement of a rug, for instance, may be the only clue to a murder. It's--it's rare!"

The little district attorney beamed. If he had found it necessary to walk across the floor just then he would have strutted. I smiled because I wanted Kennedy to show again his marvelous skill in tracing a crime to its perpetrator. I was anxious that nothing should be done to hamper him.

II

THE TINY SCRATCH

Kennedy, before his own examination of the body, turned to Doctor Blake. "Tell me just what you found when you arrived," he directed.

The physician, whose practice embraced most of the wealthy families in and around Tarrytown, was an unusually tall, iron- gray-haired man of evident competency. It was very plain that he resented his unavoidable connection with the case.

"She was still alive," he responded, thoughtfully, "although breathing with difficulty. Nearly everyone had clustered about her, so that she was getting little air, and the room was stuffy from the lights they had been using in taking the scene. They told me she dropped unconscious and that they couldn't revive her, but at first it did not occur to me that it might be serious. I thought perhaps the heat--"

"You saw nothing suspicious," interrupted Kennedy, "nothing in the actions or manner of anyone in the room?"

"No, when I first entered I didn't suspect anything out of the way. I had them send everyone into the next room, except Manton and Phelps, and had the doors and windows thrown open to give her air. Then when I examined her I detected what seemed to me to be both a muscular and nervous paralysis, which by that time had proceeded pretty far. As I touched her she opened her eyes, but she was unable to speak. She was breathing with difficulty; her heart action was weakening so rapidly that I had little opportunity to apply restorative measures."

"What do you think caused the death?"

"So far, I can make no satisfactory explanation." The doctor shrugged his shoulders very slightly. "That is why I advised an immediate investigation. I did not care to write a death certificate."

"You have no hypothesis?"

"If she died from any natural organic disorder, the signs were lacking by which I could trace it. Everything indicates the opposite, however. It would be hard for me to say whether the paralysis of respiration or of the heart actually caused her death. If it was due to poison--Well, to me the whole affair is shrouded in mystery. The symptoms indicated nothing I could recognize with any degree of certainty."

Kennedy stooped over, making a superficial examination of the girl. I saw that some faint odor caught his nostrils, for he remained poised a moment, inhaling reflectively, his eyes clouded in thought. Then he went to the windows, raising the shades an additional few inches each, but that did not seem to give him the light he wished.