had contracted the disease in the tropics. As a disease of indigenous origin, notwithstanding the considerable amount of dysentery in lunatic asylums and similar large public institutions in Great Britain, it is distinctly rare, though not so uncommon as is usually supposed. Of course this remark does not apply to those suppurations which are connected with ordinary pyæmia, with gall-stones, hydatids, pylephlebitis, and the like; it applies only to dysenteric and, possibly, if there be such a disease, to idiopathic abscess. In northern and central Europe it is much the same in this respect as in Britain. The disease is more frequent in southern Europe in Italy, Greece, the Balkan peninsula, and south Russia; it is said to be particularly common in Roumania. In eastern Asia, even outside the tropical belt, it is far from rare: thus, it is not uncommon in Japan, and it is a very notable feature of the morbidity of Shanghai and the coast of south China. In north and tropical Africa it is common enough; indeed, some of the best modern studies of the disease have been made in Egypt and in the Algerian province of Oran. In the western hemisphere there is a corresponding distribution; fairly common in the tropics, it becomes progressively rarer as we proceed north and south. It is apparently less common in the West Indies than in India and the East generally. In the southern hemisphere, although the Cape and Transvaal and the cooler parts of Australia seem to enjoy a practical immunity, the European in the Northern Territory of Australia and in the neighbouring island of New Caledonia is subject to this disease.
The apparent caprice in the geographical distribution of liver abscess is probably, in great part, explained by what has already been stated with regard to the distribution of amœbic dysentery, and to the effects of high atmospheric temperature and tropical habits on the European liver, together with the circumstance, as will be mentioned in the sequel, that the amoeba is an important, if not a principal, element in the production of tropical liver abscess.
