57 (2) The existence of numerous permanent breeding places of Neocellia stephensi in the hundreds of open house wells and a less number of masonry tanks and iron cisterns in the North Fort, adjoining the area in which construction work was being undertaken. (3) The settling down of many coolie labourers in temporary huts on the site of the new dock-works. (4) The formation of many pools of water on the upper surface of the works (not excavations) in the vicinity of the labourers' huts. (5) The gradual spread of Neocellia stephensi from the North Fort to these new breeding places. (6) The gradual spread of infection among the labourers, at first chiefly from the North Fort but afterwards from one to another. (7) The occurrence in 1907 and 1908 of climatic, economic and other conditions favouring an epidemic outbreak of malarial disease. 128. There is plenty of evidence to show that malaria existed in the North Fort long before 1904 when the docks were commenced. A medical man born and brought up in the Fort volunteered the inform- ation that he well remembers possessing an enlarged spleen as a boy and being treated for it; and ten years ago Europeans resident in flats near Elphinstone Circle repeatedly suffered from malaria, some of them so severely that they had to leave the neighbourhood. As residents in the North Fort contracted malaria years ago, it is certain that the transmitting agent must have been present. Neocellia stephensi, the transmitting agent of most of the malaria in Bombay, was found in the city in 1901, and the presence of over 600 wells and other collections of water in the North Fort, 300 of which were infested with it in 1909, makes it reasonable to assume that it has been concerned in the spead of malaria in this area for a very long period. 129. The settling of large numbers of coolies in temporary huts on the dock site was a mistake in view of the danger of epidemic disease occurring amongst them. The rule that, in malarious countries labourers should not be housed on the site of large excavation works, was first laid down by Colin over 50 years ago and it has been endorsed by many other authorities since then. Fayrer in 1902, emphasizing the precautions previously laid down by Colin, states:- "The draining of marshes, the making of canals, railway cuttings, "roads, embankments, fortifications and such like, and the cutting down of "jungle, should be executed with great precautions, and if possible at the "healthy season; the labourers are to be protected by proper shelter, "removal from the seat of labour at night,* and the free use of quinine and "proper diet while they are at work." It is probable that the failure to remove the labourers from the site of the work at night and the omission possibly of sufficiently drastic measures of prevention at the outset have been responsible for the severity of the outbreak of malaria in the neighbourhood of the new docks. 130. There is no reason to suppose that the labourers brought much infection with them, as the examination of newly arrived coolies living on the works has usually shewn them to be free both from enlarged spleen or parasites in their blood; but those resident a few months shew a considerable amount of infec- tion; and among those over a year at work nearly everyone has an enlarged spleen. In 1910 the headman of one gang volunteered the statement that of 300 working coolies who came with him from their district (Márwár) one hundred had died and another hundred had deserted their work during the preceding eighteen months. He ascribed the occurrence of fever and enlarge- ment of the spleen among his men to the water they drank at the docks and stated that in his own village the people did not suffer in this way. His ideas regarding the water were of course an error, but the examination of a dozen * The italies are mine.-C. A. B. 136-15