9. There were cases of this fever so light, that patients were said to be neither _sick_ nor _well_; or, in other words, they were sick and well half a dozen times in a day. Such persons walked about, and transacted their ordinary business, but complained of dulness, and, occasionally, of shooting pains in their heads. Sometimes the stomach was affected with sickness, and the bowels with diarrh[oe]a or costiveness. All of them complained of night sweats. The pulse was quicker than natural, but seldom had that convulsive action which constitutes fever. Purges always brought away black stools from such patients, and this circumstance served to establish its relationship to the prevailing epidemic. Now and then, by neglect or improper treatment, it assumed a higher and more dangerous grade of the fever, and became fatal, but it more commonly yielded to nature, or to a single dose of purging physic. 10. There were a few cases in which the skin was affected with universal yellowness, but without more pain or indisposition than usually occurs in the jaundice. They were very frequent in the year 1793, and generally prevail in the autumn, in all places subject to bilious fever. 11. There were _chronic_ cases of this fever. It is from the want of observation that physicians limit the duration of the yellow fever to certain days. I have seen many instances in which it has been protracted into what is called by authors a slow nervous fever. The wife of captain Peter Bell died with a black vomiting after an illness of nearly one month. Dr. Pinckard, formerly one of the physicians of the British army in the West-Indies, in a late visit to this city informed me, that he had often seen the yellow fever put on a chronic form in the West-India islands. In delivering this detail of the various forms of the yellow fever, I am aware that I oppose the opinions of many of my medical brethren, who ascribe to it a certain uniform character, which is removed beyond the influence of climate, habit, predisposition, and the different strength and combinations of remote and exciting causes. This uniformity in the symptoms of this fever is said to exist in the West-Indies, and every deviation from it in the United States is called by another name. The following communication, which I received from Dr. Pinckard, will show that this disease is as different in its forms in the West-Indies as it is in this country.