remittent in ardent climes nearer the tropic; whilst within the tropics the life of the European stranger can scarcely be valued at a week’s purchase.[15] To this destructive influence, most commonly connected with a marshy soil, the Italian first gave the name of malaria--a useful appellation, universally accepted as implying no theory; and had such fevers been found only in such localities, the inference must have followed, that a something, open to the chemist to discover, emanating or produced by these marshes, was solely and distinctly the cause of all such fevers. But now a more careful and extended inquiry shows that such fevers are not confined to those districts, but infest even the hay-field, are not unfrequent in or near woods growing on soils where marshes have ever been unknown; whilst as regards the more ardent remittents of Eastern countries, the statistics of Major Tulloch have all but destroyed the theory which would trace to marshes exclusively the fevers which in such countries set all medical treatment and all human precautions at defiance.[16] [15] This question, in so far as regards a military life, has been handled in a masterly manner by Major Tulloch. [16] In the expedition to St. Domingo, the English army forming the expedition landed 10,000 strong; they withdrew in five weeks, without striking a blow or seeing an enemy. Their numbers were reduced to 1100. See “History of the Expedition to St. Domingo,” by Dr. Maclean. This uncertainty of life from the effects of malaria must ever, I think, remain whilst the true nature of the poison is unknown; and it is with a view to discover, if possible, the circumstances under which it originates, that I undertook this difficult inquiry. Long resident in a country supposed to be an ague-producing land, I watched with much interest the social condition of a sagacious, prudent, and industrious race of men, who could thus, at one and the same time, preserve their liberty and life from the hostile assaults of furious, implacable tyrants from without, and of an insidious, invisible enemy within, walking stealthily around the habitations of men, poisoning the air of his house, his fields, and gardens. It was in Holland that a French general, writing to the great Napoleon, and complaining of the destruction of the garrisons by fever, received from him the only reply which at the time the necessities of the mighty conqueror permitted him to give--“_L’homme meurt partout_.” “Man dies everywhere,” was the only answer, if answer it could be called, to a kind-hearted commander, more touched by the calamity around him than by the exigencies of the State.