12. I mentioned formerly the sign of a _second childhood_ in the state of the appetite in old people. It appears further, 1. In the marks which slight contusions or impressions leave upon their skins. 2. In their being soon fatigued by walking or exercise, and in being as soon refreshed by rest. 3. In their disposition, like children, to detail immediately every thing they see and hear. And, 4. In their aptitude to shed tears; hence they are unable to tell a story that is in any degree distressing without weeping. Dr. Moore takes notice of this peculiarity in Voltaire, after he had passed his 80th year. He wept constantly at the recital of his own tragedies. This feature in old age, did not escape Homer. Old Menelaus wept ten years after he returned from the destruction of Troy, when he spoke of the death of the heroes who perished before that city. 13. It would be sufficiently humbling to human nature, if our bodies exhibited in old age the marks only of a second childhood; but human weakness descends still lower. I met with an instance of a woman between 80 and 90, who exhibited the marks of a _second infancy_, by such a total decay of her mental faculties, as to lose all consciousness in discharging her alvine and urinary excretions. In this state of the body, a disposition to sleep, succeeds the wakefulness of the first stages of old age. Dr. Haller mentions an instance of a very old man who slept twenty, out of every twenty-four hours during the few last years of his life. 14. The disposition in the system to _renew_ certain parts in extreme old age, has been mentioned by several authors. Many instances are to be met with in the records of medicine of the sight[71] and hearing having been restored, and even of the teeth having been renewed in old people a few years before death. These phenomena have led me to suspect that the antediluvian age was attained by the frequent renovation of different parts of the body, and that when they occur, they are an effort of the causes which support animal life, to produce antediluvian longevity, by acting upon the revived excitability of the system. [71] There is a remarkable instance of the sight having been restored after it had been totally destroyed in an old man near Reading, in Pennsylvania. My brother, Judge Rush, furnished me with the following account of him in a letter from Reading, dated June 23, 1792.