impulses all right? Good. And have you had time to study the records? Yes? What's that? Number seven? All right. I'll see you very soon and go over the records again with you. Good-bye."
"One word more," he continued, now facing us. "The normal heart traces its throbs in regular rhythm. The diseased or overwrought heart throbs in degrees of irregularity that vary according to the trouble that affects it, both organic and emotional. The expert like Barren can tell what each wave means, just as he can tell what the lines in a spectrum mean. He can see the invisible, hear the inaudible, feel the intangible, with mathematical precision. Barron has now read the electro-cardiograms. Each is a picture of the beating of the heart that made it, and each smallest variation has a meaning to him. Every passion, every emotion, every disease, is recorded with inexorable truth. The person with murder in his heart cannot hide it from the string galvanometer, nor can that person who wrote the false note in which the very lines of the letters betray a diseased heart hide that disease. The doctor tells me that that person was number—"
Mrs. Collins had risen wildly and was standing before us with blazing eyes. "Yes," she cried, pressing her hands on her breast as if it were about to burst and tell the secret before her lips could frame the words, "yes, I killed her, and I would follow her to the end of the earth if I had not succeeded. She was there, the woman who had stolen from me what was more than life itself. Yes, I wrote the note, I poisoned the envelope. I killed her."
