One of my prescriptions for longevity may startle you somewhat.  It is this:  Become the subject of a mortal disease.  Let half a dozen doctors thump you, and knead you, and test you in every possible way, and render their verdict that you have an internal complaint; they don’t know exactly what it is, but it will certainly kill you by and by.  Then bid farewell to the world and shut yourself up for an invalid.  If you are threescore years old when you begin this mode of life, you may very probably last twenty years, and there you are,—­an octogenarian.  In the mean time, your friends outside have been dropping off, one after another, until you find yourself almost alone, nursing your mortal complaint as if it were your baby, hugging it and kept alive by it,—­if to exist is to live.  Who has not seen cases like this,—­a man or a woman shutting himself or herself up, visited by a doctor or a succession of doctors (I remember that once, in my earlier experience, I was the twenty-seventh physician who had been consulted), always taking medicine, until everybody was reminded of that impatient speech of a relative of one of these invalid vampires who live on the blood of tired-out attendants, “I do wish she would get well—­or something”?  Persons who are shut up in that way, confined to their chambers, sometimes to their beds, have a very small amount of vital expenditure, and wear out very little of their living substance.  They are like lamps with half their wicks picked down, and will continue to burn when other lamps have used up all their oil.  An insurance office might make money by taking no risks except on lives of persons suffering from mortal disease.  It is on this principle of economizing the powers of life that a very eminent American physician,—­Dr. Weir Mitchell, a man of genius,—­has founded his treatment of certain cases of nervous exhaustion.

What have I got to say about temperance, the use of animal food, and so forth?  These are questions asked me.  Nature has proved a wise teacher, as I think, in my own case.  The older I grow, the less use I make of alcoholic stimulants.  In fact, I hardly meddle with them at all, except a glass or two of champagne occasionally.  I find that by far the best borne of all drinks containing alcohol.  I do not suppose my experience can be the foundation of a universal rule.  Dr. Holyoke, who lived to be a hundred, used habitually, in moderate quantities, a mixture of cider, water, and rum.  I think, as one grows older, less food, especially less animal food, is required.  But old people have a right to be epicures, if they can afford it.  The pleasures of the palate are among the last gratifications of the senses allowed them.  We begin life as little cannibals,—­feeding on the flesh and blood of our mothers.  We range through all the vegetable and animal products, of nature, and I suppose, if the second childhood could return to the food of the first, it might prove a wholesome diet.