What then were the conditions determining its local preference? Consideration of its statistics, or inspection of a cholera-map, enables one, with some confidence, to answer--a peculiar condition of soil, of which dampness is one sure and invariable character, and organic decomposition (promoted by dampness) probably another.[41] Its local affinities have much analogy to those of ague, and often appear identical in their range with the sphere of malarious infection. Our entire metropolis, built down to the very margins of a large river--of a river, too, which, at each retreating tide, exposes acres of mud saturated with the reeking sewage of an immense population, is placed generally in circumstances not unfavourable to the development of the disease; and its several parts will be liable to suffer especially, in proportion as they are exposed to these general circumstances, or to special circumstances of their own of a like nature. The lower level of districts on the south side of the river, their attendant failure of natural land-drainage, the consequent soddenness of a soil from which likewise the materials of house refuse were never efficiently removed, accounted sufficiently for the frightful epidemic mortality which prevailed in those quarters of the metropolis. [41] After three years’ further inquiry I find no reason to modify this general description: but, as regards the local circumstances which determine the specified condition of soil and atmosphere, I have been able to extend my information; and the subject is therefore better treated in my Fifth Annual Report than in the paragraphs here following above.--J. S., 1854.