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434 estimated as high as 20 to 40 per cent. Coolies and natives were alone affected; Europeans enjoyed a complete immunity. In Calcutta the disease was confined to a particular quarter; here it attacked families and groups of people, slowly extending its area, but at no time becoming generally epidemic throughout the city. A very limited epidemic of the disease appeared in Calcutta in 1901, and again in 1908-9.

Etiology.— Both sexes were attacked; children under puberty were less liable than adults; sucklings were seldom affected. The weak and the robust were equally susceptible. There are no direct observations on the germ of the disease; there is indirect evidence of its portability and of its communicability. But as to whether it is directly communicable from man to man, or whether it, or its cause, is indirectly transmitted through some unrecognized medium, has not been determined. Evidence of its capacity for remaining latent for a considerable period is supplied by the history of the successive epidemics in Calcutta, where it is said more especially to affect the Hindus. The disease could not have been a very catching one, seeing that no medical man was attacked, and that, except in the case of Mauritius, it spread but slowly.

Major Greig, who has made a special study of the disease during the epidemics in Calcutta, concludes that epidemic dropsy resembles ship beriberi, and that it is conduced to by a " one-sided " dietary of cereals from which the vitamine elements have been removed by over-milling. He remarks that the rise and fall of several of the epidemics have synchronized with periods of high-priced grain, when the poorer classes could not afford to supplement, as they do in more normal times, the cereal diet with additional articles of food. The nature of the disease is still obscure; many believe it to be nothing but beriberi, and it is possible that observers, while entertaining opposite opinions, have been dealing with two different diseases. Identification.— McLeod, after a careful analysis