The first symptoms of this fever seem identical with remittent, often well marked by periodicity, but finally reaction occurs, and it assumes a typhoid character. The disease is ushered in generally with a chill, severe at times, though usually moderate, of short duration, and rarely repeated. The chill is followed by slight fever, with increased heat of surface; but this rarely rises to any considerable height, and continues only for two or three days, when, in cases likely to prove fatal, it is succeeded by coldness of surface, etc. Sweating exists in many cases. The pulse is singular in character, but rarely rises above a hundred; the tongue is moist and white for the first few days, but as the disease advances it becomes red, smooth, shining, and dry, having a black streak in the middle. The most prominent symptoms are nausea and vomiting. In fatal cases the vomiting is persistent, and towards the termination the green biliary matter thrown up changes to a thin black fluid, having a sediment like the grounds of coffee. This is the terrible black vomit (vomita-nigra)of yellow-fever. The bowels are generally costive, and the abdomen tender upon pressure. Severe headache generally exists, and the countenance bears a singular expression, in which a smile seems to play upon the lips, but the rest of the face bears a wild or sad look. Restlessness is common to this disease night and day. Blood often escapes from the nose, gums, ears, stomach, bowels, and urinary passages. The skin bears a tinged color similar to that in jaundice. The disease appears both endemically and epidemically. At first the disease is hard to recognize, presenting but the usual symptoms of fevers in their incipient stage, with no symptoms to distinguish the disease, or, if any, very obscure; but when the severe pain in the back and loins exists, the conjunctiva injected, and a red flush of the face and forehead is present, the identity of the disease is no longer in doubt, especially when extraneous circumstances, calculated to suggest the probability of an attack of yellow-fever, are also present.

TREATMENT. -- In the early stage of the attack it should be treated, as regards medicines, the same as a case of malarial fever. If any derangement of the stomach exists, a gentle emetic is proper; this rouses the nervous system from its lethargy, promotes the action of the liver, and, by determining the blood to the surface, restores the capillary circulation. The best emetic for this purpose is lobelia combined with boneset. The febrile stage requires a thorough bath with tepid water and whiskey over the entire surface, with friction by rubbing with a towel or the hand. Large mustard poultices should be placed over the spine and abdomen. Immediately upon the decline of fever, if the symptoms denote urgency, administer the antiperiodic remedies advised in intermittent and remittent fever. The sulphate of quinia may be combined with tannin, because the astringent properties of the tannin have a beneficial effect in subduing inflammatory action of the mucous membranes. This remedy should not be delayed a moment if the patient is in a period of prostration, and its retention by the stomach should be favored by anodynes, carminatives, or stimulants, as the case may require. Oil of turpentine and Cayenne pepper can also be combined with advantage in this disease. The strength of the patient must be supported by every means that can be employed -- gruel and weak animal broths, bread-water, my nutritive fluids, milk and water, etc., are important means for this object. The revulsive influence of a blister over the stomach is of great service in this state. If reaction is induced and convalescence established, the remaining strength of the patient must be careully husbanded by proper tonics and wholesome and digestible diet, increasing the quantity as the patient gains strength.

All exposed to yellow-fever should avoid the night-air and sudden changes of temperature; they should sleep in the highest part of the house; be moderate in taking exercise; they should take nutritious but not stimulating food, and never expose themselves to infected air with empty stomachs or when fatigued.