According to Pettenkofer, Ford and others, an excessive amount of water in the soil is injurious to health by the effects of dampness. It favors the decomposition of organic matter in the soil, and the evolution of unhealthy effluvia. The water is liable to become polluted, especially when it is the source of supply of water in wells used for drinking purposes. The soil is so damp in Indianapolis, that houses built close to the ground are known to be very unhealthy. At least four-fifths of all the houses in the city are too near the ground, to insure perfect immunity from dampness, and its blasting influences to health. In the construction of dwellings, care should be taken to provide the most efficient means for excluding dampness from the foundation walls and basement floors; and the soil should be rendered drier by underground drainage. Fox says, it is very unwise to allow the soil close to houses to be defiled by filth; for the fires of a house creating a force of suction, draw into the house the air contained in the surrounding soil, as well as of that on which it is built. The popular impression, that the atmosphere ends where the ground begins, is a very widely spread delusion. Most soils are more or less porous. A house built on gravelly soil stands on a foundation composed of a mixture of two parts of small stones and one part of air. The air may give place to any gas or to water. Zymotic diseases have been known to arise from the emanations of soil polluted by excreta, and impurities from sewers and drains and all other filth. Poisoning by breathing the gases generated in sewers and cess-pools is not uncommon. In reference to this point, Dr. Jno. Simon says: “The ferments so far as we know them, show no power of active diffusion in dry air; but as moisture is their normal medium, currents of humid air (as from sewers and drains) can lift them in their full effectiveness, and if into houses or confined exterior spaces, then with their chief chances of remaining effective; and ill-ventilated, low-lying localities, if unclean as regards the removal of their refuse, may especially be expected to have these ferments present in their common atmosphere as well as of course teeming in their soil and ground water.” Indianapolis is in the bottom of a basin, the rim of which rises sixty or seventy feet all round it, east of White river; in some places as at Crown Hill to three times that height. [Illustration]