secure treatment before this time, he should take a single dose of twenty grains of quinine. To children may be given a daily amount of quinine equal to one grain for each year of their age. In the severe forms of remittent and pernicious types of malaria it may be necessary for the patient to take as much as thirty grains of quinine every three days or so to cut short the attack. But, unfortunately, the digestion may be so poor that absorption of the drug does not occur, and in such an event the use of quinine in the form of the bisulphate in thirty-grain doses, with five grains of tartaric acid, will in some cases prove effective. Chronic malaria is best treated with small doses of quinine, together with arsenic and iron. A capsule containing two grains of quinine sulphate, one-thirtieth grain of arsenious acid, and two grains of reduced iron should be taken three times daily for several weeks. =YELLOW FEVER.=--This is a disease of tropical and subtropical countries characterized by fever, jaundice, and vomiting (in severe cases vomiting of blood), caused by a special germ or parasite which is communicated to man solely through the agency of the bites of a special mosquito, _Stegomyia fasciata_. =Distribution.=--Yellow fever has always been present in Havana, Rio, Vera Cruz, and other Spanish-American seaports; also on the west coast of Africa. It is frequently epidemic in the tropical ports of the Atlantic in America and Africa, and there have been numerous epidemics in the southern and occasional ones in the northern seacoast cities of the United States. The last epidemic occurred in the South in 1899. Rarely has the disease been introduced into Europe, and it has never spread there except in Spanish ports. The disease is one requiring warm weather, for a temperature under 75 deg. F. is unsuitable to the growth of the special mosquito harboring the yellow-fever parasite. It spreads in the crowded and unsanitary parts of seacoast cities, to which it is brought on vessels by contaminated mosquitoes or yellow-fever patients from the tropics. Havana has heretofore been the source of infection for the United States, but since the disease has been eradicated by the American army of occupation, that danger has been removed. Yellow fever is not at all contagious in the sense that a healthy person can contract the disease by contact with a yellow-fever patient, or with his discharges from the stomach, bowels, or elsewhere, and is probably only communicated to man by the bite of a particular kind of mosquito harboring the yellow-fever organism in its body. Both these facts have been incontestably proved,[12] in part by brave volunteers from the United States Army who submitted to sleep for twenty-one days on clothes soiled with discharges from patients dying of yellow fever, and escaped the disease; and by others living in uncontaminated surroundings who permitted themselves to be bitten by infected mosquitoes and promptly developed yellow fever.