the flabby skin of Pitts as well as the small and sluggish pupils of his eyes.
He completed his test in silence and excused himself, although as we went back to the kitchen I was burning with curiosity.
"What was it?" I asked. "What did you discover?"
"That," he replied, "was a sphygmomanometer, something like the sphygmograph which we used once in another case. Normal blood pressure is 125 millimetres. Mr. Pitts shows a high pressure, very high. The large life insurance companies are now using this instrument. They would tell you that a high pressure like that indicates apoplexy. Mr. Pitts, young as he really is, is actually old. For, you know, the saying is that a man is as old as his arteries. Pitts has hardening of the arteries, arteriosclerosis—perhaps other heart and kidney troubles, in short pre-senility."
Craig paused: then added sententiously as if to himself: "You have heard the latest theories about old age, that it is due to microbic poisons secreted in the intestines and penetrating the intestinal walls? Well, in premature senility the symptoms are the same as in senility, only mental acuteness is not so impaired."
We had now reached the kitchen again. The student had also brought down to Kennedy a number of sterilised microscope slides and test-tubes, and from here and there in the masses of blood spots Kennedy was taking and preserving samples. He also
