In the same way eggs of the two common tapeworms pass out with the feces, and the offal containing them being eaten by hogs in the one case, or being scattered in the vicinity and taken in with grass by cows in the other, have their shells dissolved off as soon as they reach the stomachs of these animals, and there are liberated small embryos that bore through the walls of the stomach and later find their way into the muscular tissues of these beasts, and there lie dormant until eaten by man with imperfectly cooked meat; after being swallowed, the embryo parasite passes to the intestine and soon becomes a fully developed tapeworm. Particular reference at this point should be directed to the evil effects, which are even still greater than those that come from the privy, of permitting children and hired helpers to scatter their feces indiscriminately in corners of the yard, the apple-orchard, or in the horse-lot; under such circumstances, where hook-worm disease is once introduced, the soil in the course of a short time becomes thoroughly permeated with the embryos of this worm, and, as a consequence, all of the children who play in the infected area barefooted, as is customary in the country, are sooner or later infected with these parasites. It is thus seen that soil-pollution from fecal material is a most dangerous thing, and, particularly in the southern portion of the United States, deserves the most earnest consideration of everyone. We should see to it that our children only evacuate their bowels in properly constructed closets; and it is the duty of the head of every family to provide such a place for the accommodation of those who are dependent on him. _Proper Construction of Out-door Privies._--The most practical and generally satisfactory device heretofore invented for the disposal of the sewage of communities unprovided with water-works is what is known as the Rochdale, or dry-closet, system. By this system a privy, at a distance from the dwelling, is constructed in the ordinary manner, with the exception that instead of being open at the back it is tightly closed. In the space beneath the seat receptacles are placed for receiving the urine and feces. These may consist of pails of wood or better of galvanized iron; or a single box occupying the whole space. If wooden receptacles are used, they should be thoroughly coated on the inside with tar, to prevent both leakage and the soaking of the liquids into the wood. One such structure, which the writer knows has been wholly satisfactory has a brick foundation with walls two feet high around the front and sides, within which rests a shallow tarred box. It ensures perfect cleanliness. In any case this space under the seat is tightly closed, being guarded by doors that open outward, through which the pails or box may be introduced and removed for emptying.