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In every community where it is practicable an efficient scavenger service under proper official direction should be provided for the care of privies and for the disposal of night soil. It has been found that when this work is left entirely to private families a sanitary condition of the privies in many instances will not be maintained.
Whatever can be done in simplification and in lessening expense and labor in the installation and maintenance of a safe system for the disposal of human excreta will increase the chances for its adoption.
THE L. R. S. PRIVY.1
An effort has been made to construct a device which will decrease the disadvantages and at the same time increase the advantages connected with the older types of privies. The results obtained from various experiments have been applied to an apparatus known as the L. R. S. privy. (Figs. 10, 11, 12, and 13.)
This apparatus consists of the following parts:
(1) A water-tight barrel or other container to receive and liquefy the excreta.
(2) A covered water-tight barrel, can, or other vessel to receive the effluent or outflow.
(3) A connecting pipe about 2 inches in diameter, about 12 inches long, and provided with an open T at one end, both openings of the T being covered with wire screens.
(4) A tight box, preferably zinc lined, which fits tightly on the top of the liquefying barrel. It is provided with an opening on top for the seat, which has an automatically closing lid.
(5) An antisplashing device, consisting of a small board placed horizontally under the seat about an inch below the level of the transverse connecting pipe. It is held in place by a rod, which passes through eyes or rings fastened to the box and by which the board is raised and lowered. The iiquefying tank is filled with water up to the point where it begins to trickle into the effluent tank.
As an insect repellent a thin film of some form of petroleum may be poured on the surface of the liquid in each barrel.
Practical working of the apparatus.-When the privy is to be used, the rod is pulled up so that the antisplashing board rises to within about 1 inch below the surface of the water. The fecal material falls into the water, but this board prevents splashing, and thus overcomes one of the greatest objections thus far raised to the wet system. After use the person sinks the antisplashing board by pushing down the rod, and the fecal matter then floats free into
Although some of the fecal matter floats, it is protected both from fly breeding and fly feeding in the following ways: First, by the automatically closing lid; second, by the water; third, by the film of oil; and fourth, by having the apparatus located in a screened place, which should be done for additional safety. The film of oil also prevents the breeding of mosquitoes in the barrel. Accordingly, so far as the privy as a breeding or feeding place for flies and mosquitoes is concerned, the model in question completely solves the problem.
1 Lumsden, Roberts, and Stiles: "Preliminary note on a simple and inexpensive apparatus for use in the safe disposal of night soil." Public Health Reports, 1910, Nov. 11. v. 25 (45), pp. 1623-1629. Stiles and Lumsden: The Sanitary Privy. Farmers' Bulletin 463 (U. S. Department of Agriculture), pp. 17-21.
FIG. 9.-A SINGLE SANITARY DEVICE CONSISTING OF A
The board A is sawed so as to fit snugly around the top of the recep-
The fecal material becomes fermented in the water and gradually liquefies. As the excreta settle the level of the liquid is raised and the excess flows into the effluent tank, where it is protected from insects by the cover and a film of oil. This effluent may be allowed to collect in the tank until it reaches the level of the connecting pipe, when it may be safely disposed of in any one of the following ways:
(1) Heat.-Heat to boiling and then bury, or, if desired, it may be safely used after boiling as fertilizer.
(2) Chemical disinfection and subsequent burial.—A suitable combination of these two methods may be used certainly with reasonable safety.
(3) Sewers. In partially sewered towns the effluent may be emptied into the sewers.
It is thus seen that this device appears to meet the following requirements: (1) It solves the fly problem and the mosquito problem, so far as the privy is concerned.
(2) It liquefies fecal material and reduces its volume, so that it may be safely disposed of more easily and cheaply than the night soil from other types of privies.
(3) It reduces odor.
(4) It reduces the labor of cleaning the privy and makes this work less disagreeable.
(5) It is of simple and inexpensive construction.
This device has been in constant operation in one of the workrooms on the main floor of the Hygienic Laboratory at Washington for 15 months and has been found entirely satisfactory. From July 12, 1910, to April 1, 1911, namely, 262 days, it was used 738 times, giving an average of 2% defecations (with urination) per day. The amount of overflow (effluent) from the liquefying tank was 59 gallons. The liquefying tank itself consists of an ordinary watertight 40-gallon whisky barrel, and it was not necessary during the period of experimentation (8 months) either to add water or empty it.
Tests of this device are now being made in out-of-doors privies in order to determine the effect upon it of varying conditions of temperature and humidity. Tests are also being made to bring out whatever objectionable features may arise in connection with its general use and to determine the simplest methods of managing the device so that any family may keep it in proper working order without difficulty.
The handle of the antisplasher should come up through the seat board at the side of the hole. By this arrangement the antisplasher can be raised entirely out of the water and thus used to sink the toilet paper and fecal matter if too much floats on the surface. (Fig. 12.)
As an effluent tank various receptacles can be utilized. If an iron pot is used, it can be placed on stones or provided with legs, so that a space is left under it to permit the building of a fire and the effluent easily and cheaply disinfected by heat.
As a liquefying tank one may use either a barrel (fig. 10) or an iron tank, or a box (fig. 11), or a brick vault, or a concrete vault (fig. 13). Whatever is used for this purpose must be strictly water-tight. Iron or concrete will cost more than wood, but on account of greater durability will be more economical in the long run.
The larger the family the larger the liquefying tank must be. A 40-gallon barrel, such as a whisky or oil barrel, seems sufficient for a family of three adults. For a larger family the capacity should be increased by using two 37856-14-4
or more barrels or one larger receptacle, in the proportion of about 40 gallons' capacity to every three or four adults in the family.
One advantage the device possesses is that with very little expense it can be put in the outhouses already in use; in fact, it can be placed in any of the outhouses on the farm, such as barn or woodshed, and thus save the expense of building for this special purpose. Wherever put, it is very important to have
it in a place screened against flies.
From the out-of-door experiments thus far it can be readily foreseen that two factors come into consideration which have not been found important in the indoor privy, namely, evaporation and changes of temperature.
In cold weather the contents of the tank may freeze, or, due to lessened fermentation, gradually become thickened.
The evaporation out of doors will vary greatly with the wind, humidity, and temperature in different regions, and the greater the evaporation the thicker the material in the liquefying tank becomes.
Should such thickening occur the odor will increase, and it will be necessary to add water to the liquefying tank. In order to prevent such thickening it may be found necessary in some instances to add water from time to time. Just how often and how much water should be added under adverse conditions has not yet been determined, but, so far as can be foreseen at present, probably a bucketful (about 2 gallons) added once a week will be sufficient for a single barrel used by a family of three or four adults.
Experiments have conclusively demonstrated that the principle of the L. R. S. privy is good. The details regarding the addition of water must be determined experimentally in different localities. Any intelligent man should be able to determine this point for his own locality.1
If this type of privy is managed fairly intelligently, the indications are that the liquefying tank will rarely need cleaning, probably not more than once a year. When cleaning does become necessary, this can be done in several ways: The tank may be taken out, and its contents burned or boiled; or the contents may be pumped or dipped out and burned or boiled; or a considerable amount (several barrelfuls) of water can be poured gradually into the liquefying tank and the sludge thoroughly stirred until it runs over into another vessel. In the experimental L. R. S. privy the only paper used has been the regular toilet paper. This has liquefied with sufficient promptness. If heavier paper (such as newspaper) were used, this would break up more slowly, and allowance for it might have to be made by increasing the capacity of the tank. It is well to bear in mind the fact that the ink on newspaper is likely to irritate the skin. Corncobs and similar objects would certainly interfere materially with the successful working of any apparatus of this kind.
The device is better adapted for sections having warm or moderate climates than for those having long cold winters. But if the apparatus were kept in a room with a temperature maintained above the freezing point, or if the lique fying tank were sunk in the ground below the freezing line, or embedded in a pile of stable manure, or otherwise protected against freezing, the indications are that it could be operated successfully even in cold climates. Since the same outhouse may be operated either as a pail-system privy or as an L. R. S. privy, it probably would be convenient in some localities to alternate the systems with the seasons, the L. R. 8. system being used during the warm-weather months, which are the months of greatest danger from excreta-borne infections, and the pail system during the cold-weather months.
It should be understood that the 1. R. S. privy is described simply as a type and may de modified to suit varying conditions.