PLUMBING. 130 PLUMBING. of water, generally from a tank located above the closet. Tlie discharfic is generally effected by pulling a hanging chain attached to a lever and valve, but in the case ot closets in public places the tanks may discharge automatically. Recently, however, attachments have been intro- duced for flushing water-closets without the use ftef- -.7 "i Washout. Washdown. TYPES OF WATEB-CL08ET8. of a tank, the water supply being controlled by a valve, operated by a short lever, near the closet seat. In eitlier case the water tluis liberated displaces the water previously standing in the bowl or hopper of the closet or else sets it in mo- tion by siphonic action, carrying the wastes with it. By this means the closet is kept fairly clean, particularly the most exposed portions, and the parts not thoroughly clean are always wet. There is an almost endless variety of closets. Some of the most approved patterns are shown in section by the accompanying illustrations. Water-closet flush tanks are generally of wood. lined with copper, and provided with a float valve, a water supply, and a tlush pipe. The closet seat is of hard wood. Urinals are pro- vided in public places, and consist of either bowls or vertical slabs of non-porous material, inclosed in stalls and provided with flushing water. Latrines are a series of water-closet stalls connected with a long trough or common flushing chamber below. They are chiefly em- ployed for barracks and institutions. The terms bathroom and water-closet are frequently em- ployed to designate the compartments which con- tain a bathtub, water-closet, and set w,i|Shbowl. Such roo7us shoiild always open to the outer air, or at least into a large air-shaft, and be well lighted, ventilated, and wanned. Sill or hose cocks are faucets or valves, with a provision for attaching hose, provided at convenient points for sjjrinkling lawns ami washing sidewalks. In some loc^ilities they, or the hose so used, are called pave washes. HorsE Sewerage or Drainage includes every- thing required to remove fouled water from the house to the sewer. The pipes from each sepa- rate fixture are known as tcaste pipes; they run to one or more soil pipes, the soil pipe being the vertical run of pipe from the highest fixture to the cellar: the house drain extends from the foot of the soil pijie to a point near the cellar wall, and the house seirer from the latter point to the street sewer. Waste jiipes, particularly short runs from washbowls and minor fixtures, may be of lead, but, generally sjjcaking, cast or wrought iron 's preferable for ini])ortant wastes. All soil pipes and the hou.se drain should also be of cast iron. Heavy pipe should be used throughout. The house sewer should be of extra heavy iron through and a short distance beyond the founda- tion, after which vitrified clay is permissible. All soil and waste pipes should be carried up through the roof. Traps are placed below each fixture and a main trap is generally set just in- side the cellar wall. All main traps should have fresh air inlets or a pipe extending from the inner end of the trap to the outer air. This pro- vides for a circulation of air through the house drain and soil pipe. An increasing numlier of sanitary engineers favor the omission of the main trap, thus insuring a thorough ventilation of the house and street sewerage system through the numerous soil pipes at one extremity and the street manholes at the other. The object of a trap is to prevent foul air from the house or street sewerage system from entering the house. To this end the simplest and most common prac- tice is to form a water seal by making a bend in the pipe shaped like the letter U or like the letter S, the former being called a U-trap and the latter an Strap. Bell traps are formed by inverting a bell or cup over the upper and open end of a pipe, the whole being so adjusted that the edge Main Drain or House Trap Grease Trap. TYPES OF TBAP8. of the pipe is always submerged. Grease traps may be described as enlargements on waste pipes- j to retain grease instead of allowing it to pass on and clog the sewers. They are most commonly used on the waste or drain pipes of large
