3. Malignant and mortal epidemics are often preceded by uncommon sickness and mortality among certain birds and beasts. They have both appeared, chiefly among wild pigeons and cats in the United States. The mortality among cats, previous to the appearance of epidemics, has been taken notice of in other countries. Dr. Willan says it occurred in the city of London, between the 20th of March and the 20th of April, in the year 1797, before a sickly season, and Dr. Buneiva says it preceded a mortal epidemic in Paris. The cats, the doctor remarks, lose, on the second day of their disease, the power of emitting electrical sparks from their backs, and, when thrown from a height, do not, as in health, fall upon their feet[13]. [13] Medical Journal, vol. iv. 4. The common house fly has nearly disappeared from our cities, moschetoes have been multiplied, and several new insects have appeared, just before the prevalence of our late malignant epidemics. 5. Certain trees have emitted an unusual smell; the leaves of others have fallen prematurely; summer fruits have been less in size, and of an inferior quality; and apples and pears have been knotty, in the summers previous to several of our malignant autumnal fevers. Dr. Ambrose Parey says, an unusually rapid growth of mushrooms once preceded the plague in Paris. II. The premonitory signs of an approaching malignant epidemic in the human body are, 1. A sudden drying up, or breaking out of an old sore; fresh eruptions in different parts of the body; a cessation of a chronic disease, or a conversion of a periodical into a continual disease. Of this there were many instances in Philadelphia, in the year 1793. 2. A peculiar sallowness of the complexion. This was observed to be general in Philadelphia, previous to the yellow fever of 1793. Dr. Dick informed me, that he had observed the same appearance in the faces of the people of Alexandria, accompanied in some cases with a yellowness of the eyes, during the summer of 1793, and previous to the appearance of a violent bilious fever on the banks of the Potomac. 3. I have observed one or more of the following symptoms, namely, head-ach; a decay, or increase of appetite; costiveness; a diminished or increased secretion of urine; a hot and offensive breath[14]; constant sweats, and sometimes of a f[oe]tid nature, or a dry skin; wakefulness, or a disposition to early or protracted sleep; a preternaturally frequent pulse; unusual vivacity, or depression of spirits; fatigue and sweats from light exertions; hands, when rubbed, emitting a smell like hepar sulphuris; and, lastly, a sense of burning in the mouth; to be present in different persons, during the prevalence of our malignant epidemics.