Even the surface of the soil when overloaded with sewage loses partially its power of purifying the organic matter. After sufficient rest, such an overloaded soil regains its original power. The purifying activity of the soil from a sanitary aspect is the same as that governing fertility from an agricultural standpoint, hence any further discussion of this subject is unnecessary.
A hint as to the proper disposition of waste, excrement, etc., is furnished by what is stated above concerning the purifying capacities of the earth's surface. Waste, night soil, etc., should be deposited with proper precautions on or immediately below the surface of the soil, where it may perform the double function of ridding the household of a nuisance and of enriching the soil itself. This leads us to a consideration of the best means of taking care of the household wastes. These are, in general, of three classes: First, fecal matter; second, kitchen and chamber slops; and third, miscellaneous rubbish and ashes.
NIGHT SOIL.
The proper disposition of fecal matter or night soil in the country has been one of the most pressing and vexatious problems of modern sanitation. Many plans have been suggested, much apparatus has been invented to meet the difficulty, but opinions not only differ but change from year to year and have led to different practices in different countries. Moreover, different climatic conditions and the divergent tendencies of rural populations in the various sections of our own country make it impossible to apply the same scheme to the whole country. Different degrees of prosperity and wealth, even in the same locality, will bring into use widely different schemes to accomplish the same end. There are in use several systems—
The privy.—The old-fashioned privy, at present still quite a common thing even in cities, is, perhaps, the most favored method of disposing of fecal matter in the country. A pit is dug and a small building set over it. The excrement deposited in it slowly fills it up. The fluids and the solids dissolved by them penetrate the subsoil and diffuse themselves in the ground. Rarely is such a pit cleaned out. Another is dug and the old one covered up. In this way the ground becomes overloaded with refuse organic matter. It is even stated on good authority that such collections of fecal matter have been found under the dwelling; also, that the privy vaults have been dug until the current of ground-water was reached which was to facilitate the removal of the excrement. It is difficult to conceive a more pernicious custom, or one more certain to pollute the drinking water. The privy vault is the most rudimentary way of getting rid of night soil, and its dangerous features are too plain to be referred to.
The cesspool.—Next comes the cesspool, which is usually connected with a water-closet, and may also receive the slops from the kitchen.
These are constructed in two ways, either as water-tight receptacles or as simple pervious pits differing in no way from the privy vault excepting, perhaps, in their more dangerous tendencies. All sanitary authorities agree in condemning the leaky cesspool as a most shiftless and dangerous method of getting rid of sewage. In most countries they are prohibited by law in populous communities. In exceptional cases, leaky cesspools may do no harm, as in an isolated house in the country whose cesspool is built at a considerable distance both from the house and the well. The safe distance from any well it would be difficult to state, because that would depend on the character of the subsoil and the general slope of the land. In any case, the cesspool should be on lower ground than the well, as the current of the ground water feeding the latter, usually but not always, conforms to the slope of the surface. A fair estimate of the least allowable distance between well and cesspool would be 100 feet. Soluble salts from sewage might still find their way into the well water, but it is quite improbable that disease germs could penetrate the soil for such a distance except where fissures and cracks may be present.
Fig. 2.—Portable earth closet. A, the pail to receive the excrement; B, the urine-separating receptacle hanging on the open door; C, mouth of the hopper conveying the dry-earth or ashes from reservoir D upon the night soil in A.