=Climate and Acclimatization.=--In view of the rapid growth of West Indian and South American commerce and the considerable emigration to Cuba and neighboring islands, which our present relations with them will probably bring about, the following extracts from an editorial in the London Lancet are of interest: "The American nation has entered upon a new and, in a sense, imperial policy, which may be regarded as forming an epoch in its history. This brings it face to face with the problem of colonization and acclimatization--a problem which we have had to confront long ago and toward the solution of which we have ever since been slowly fighting our way by following on the lines of the best practical measures of hygiene known to us. 'The white man's burden' has proved a tragical one in its drain on the life of the young manhood of this country, notwithstanding the very large measure of success which has attended our sanitary efforts in this direction. The Americans, having taken up their burden, will, no doubt, like the practical people they are, set about their task in a practical way. The four principal factors in the production of climate, according to Buchan, are distance from the equator, height above the sea, distance from the sea, and prevailing winds. The equatorial region has the most equable climate; tropical regions have much greater variations of temperature than those near the equator, and have a hot and cold or dry and rainy season. The isothermal lines of mean temperature do not supply a graduated measure of the effects of temperature on animal life. So far as climate is concerned, no single meteorological influence appears, however, to equal the effect of temperature upon health, and its range is of more importance than its mean. The European under a tropical climate suffers from anæmia, diseases of the digestive system, especially of the liver, from malaria, dysentery, typhoid fever, and yellow fever. It is not at all easy to say, however, how much of the excess of mortality of Europeans in tropical and subtropical countries is simply attributable to climatic heat _per se_, and is consequently inevitable and not the effect of malaria, or how much of it is the direct consequence of habits of life and of the neglect of sanitary laws and of personal hygiene. As Arnould rightly said, the _habitudes alimentaires_ of the Anglo-Saxon constitute one of the stumbling-blocks to health, but by far the most important is malaria, compared with which the rest are relatively insignificant. Mr. Chamberlain was right when he said the other day that 'the man who shall successfully grapple with this foe to humanity and shall find a cure for malarial fever and shall make the tropics livable for the white man, will do more for the world and more for the British Empire than the man who adds a new province to the wide dominions of the Queen.'"