I AM, by nature, tremendously energetic. Over matters that interest me, I conceive an almost hectic enthusiasm. When at work on my favorite study, this energy, this enthusiasm, drives me on to concentrated and consuming labors which no mere human mechanism can long endure. It is no wonder then, that toward the beginning of the month of June, of the year just passed, I began to feel that my physical powers were fast on the ebb. I appealed to my friend and physician, Dr. Charles Courtenay. He examined me — and shook his head in grave silence...