"Well, first of all, we've given the old people plenty of physical jerks, embracing movements in every joint—fingers, elbow, neck—waist, knees, toes, ankles, spine—and so on. . . . They've gone in for dancing, too. Jigs, reels, clog-dancing, hornpipes . . ."
"It all sounds very hot and perspiring!" observed Gran'pa.
"Did you think so when you saw them just now?"
"No! I can't say that I did. On the contrary, they looked astonishingly cool and fresh!"
Dr. Martin beamed with pride.
"They'd come straight from an hour's drill in the gymnasium," he remarked succinctly.
"You amaze me!" conceded Gran'pa. "Well, what else have you done? 'Jerks' alone wouldn't have produced such a—miracle."
"I suppose that you've heard of the latest theory, glandular stimulants?" asked Dr. Martin.
"Vaguely! Isn't it potashes, or something?"
"Yes, a colloidal, radioactive potash. It works with extraordinary rapidity and, what is most important, it seems to stimulate all the glands in equal proportion. I believe that coördination of effects is a vital necessity to any process of rejuvenation. That's why I am not particularly in favor of grafting only one type of gland, such as the thyroid. The result may not be lasting. You may easily develop one part of the organism at the expense of the rest."