Surface-streams also occasionally supply drinking-water in rural districts, and while the use of such waters may not always be attended by danger, their contamination by disease-producing germs is much more to be feared than when they are derived from wells or springs; where streams arise from and keep their course through uninhabited districts the probabilities are strong that their waters are pure and fit for use, but where they run through cultivated fields, and particularly where they pass in the neighborhood of houses, their waters should never be looked upon as being drinkable,--except after being boiled or properly filtered. Inasmuch as adequate filtration is exceedingly difficult to carry out, and requires a somewhat extensive and costly plant, this is, as a rule, not feasible for the dweller in country districts, and boiling, therefore, remains the only satisfactory method of rendering the water fit for use where doubt exists as to its purity. _Location of Pens and Stables for Animals._--Animals should always be housed at some little distance from the dwelling. While it is true that man does not often contract directly diseases from hogs, sheep, horses and cattle, there are some maladies of a most serious character that come to us in this way, and we should, therefore, always guard against their occurrence by removing ourselves as far as is possible from sources of possible infection. The matter also has an aesthetic side, as odors of a disagreeable character may prove very annoying where animals are kept too close to the house. It is likewise of importance that stables should be, if possible, on lower ground than the dwelling, since during rains materials from their dung may be washed around and under the house, and may possibly gain access to the well. Every care should be taken to keep hog-pens and stables clean, since otherwise very foul smells are engendered that oftentimes find their way to neighboring houses. There is also a suspicion that some of the germs that produce disease find the conditions suitable for their stables and pig-sties. In this connection it might be well to warn those unacquainted with the subject against the _all too common practice_ of close association with dogs, since it is well established that in addition to hydrophobia they may transmit, while apparently in perfect health, maladies of a deadly character to the human being. It cannot be too often emphasized that the less intimate our association with the lower animals is, the greater the likelihood of our escaping many serious diseases. FOOTNOTE: