The year I wrote "The Jungle" I had my first summer cold. It was haying time on a farm, and I thought it was a kind of hay-fever. I would sneeze for hours in perfect torment, and this lasted for a month, until I went away to the sea-shore. This happened again the next summer, and also another very painful experience; a nerve in a tooth died, and I had to wait three days for the pain to "localize," and then had the tooth drilled out, and staggered home, and was ill in bed for a week with chills and fever, and nausea and terrible headaches. I mention all these unpleasant details so that the reader may understand the state of wretchedness to which I had come. At the same time, also, I had a great deal of distressing illness in my family; my wife seldom had a week without suffering, and my little boy had pneumonia one winter, and croup the next, and whooping-cough in the summer, with the inevitable "colds" scattered in between. After the Helicon Hall fire I realized that I was in a bad way, and for the two years following I gave a good part of my time to trying to find out how to preserve my health. I went to Battle Creek, and to Bermuda, and to the Adirondacks; I read the books of all the new investigators of the subject of hygiene, and tried out their theories religiously. I had discovered Horace Fletcher a couple of years before. Mr. Fletcher's idea is, in brief, to chew your food, and chew it thoroughly; to extract from each particle of food the maximum of nutriment, and to eat only as much as your system actually needs. This was a very wonderful idea to me, and I fell upon it with the greatest enthusiasm. All the physicians I had known were men who tried to cure me when I fell sick, but here was a man who was studying how to stay well. I have to find fault with Mr. Fletcher's system, and so I must make clear at the outset how much I owe to it. It set me upon the right track--it showed me the goal, even if it did not lead me to it. It made clear to me that all my various ailments were symptoms of one great trouble, the presence in my body of the poisons produced by superfluous and unassimilated food, and that in adjusting the quantity of food to the body's exact needs lay the secret of perfect health.