Closets are operated with pull or push-button tanks requiring the attention of the user; and are also made of the seat-action type. Children are likely to be forgetful, and visitors to public toilet rooms indifferent, to such an extent that automatic closets are desirable for public places and schools.

Closets are fitted with two styles of tanks - one placed about 7 feet from the floor and serving with a flush pipe never more than 1} inches in diameter; and the other placed low down, as close to the bowl as connections will permit. Examples of the high-tank and low tank arrangements are shown in Figs. 41 and 42, respectively. The low tanks are wider and deeper than the high style, but d not extend out from the wall so much. The low position delivers the water at much less velocity than the elevated style, and, to secure the utmost speed and the volume necessary, the flush connection is never less than 2-inch in a low-tank closet. The rim and jet channel are proportionately larger in bowls intended for use with low tanks. High tanks are about .17 by 9 by 10 inches. Sheet lead and sheet copper are used for closet-tank linings. Some kinds of water, through galvanic action, attack the soldering of the seams in copper-lined tanks with more

Fig. 40. Closet with Base Flange.

Support, and with Lugs for effect than where lead alone is used. Generally, however, copper-lined tanks give satisfaction if the copper is heavy enough (12 to 16 oz.) and properly put in. Some makers lock-seam the linings water-tight, and solder on the outside before placing the copper in the wood case.

Attaching Seat.

On account of the greater depth of low tanks, swelling of the wood case has, doubtless, been the cause of most of the trouble experienced with this type. When put together in the factory, the wood is very dry, and after being used for a short time, increases in height as a result of swelling from dampness. If the lining be tacked to the wood at bottom and top, injury is sure to result. Tacking at the top only is open to similar objections. It is now the practice to omit fastening the lining. Cast-iron tanks enameled two coats in and out give excellent service and so far have caused no trouble from sweating.. Iron tanks with sheet metal interior lining have also proven satisfactory. Very great care has been found necessary with ball cocks for low tanks, in order to secure proper after-fill, the flush connection being too short to aid much in resealing the bowl with its drainings Low tanks flush with much less noise than high ones, and permit placing the closet under windows and low ceilings. Low ones require more width on account of the tank, and more depth from the wall to the front, as the seat and lid must be placed far enough forward to be thrown back and remain leaning against the front of the tank. Low tanks are provided with ventilated covers; while the high pattern which is out of children's reach, is left open at the top. The fewer working parts in a tank, the less likely it is to get out of order.

Fig. 41. Modern High Tank Closet.

Courtesy of Federal-Huber Company, Chicago

Fig. 42. Modern Low Tank Closet.

Courtesy of The Trenton Potteries Company, Trenton, New Jersey

A type of seat-action after-wash closet very seldom placed in. private houses, is that with closed metal tank, as represented in Fig. 43. Depressing the seat opens a valve in the supply, and the water passes up through a flush pipe into a closed tank. The air in the tank is compressed until the air-pressure counterbalances that of the water. When the seat is released, the supply valve closes and a valve is opened, establishing communication between the closet and the tank. The compressed air then expels the water in the tank, flushing the closet just as a large supply with corresponding pressure would do without a tank. Closed-tank closets depend on pressure. The space occupied by the air in the tank is inversely proportional to the pressure; hence, even in heavy pressure, considerable of the tank's capacity is yet occupied by air when equilibrium is established; and the less the pressure, the smaller the amount of water it is possible to get into the tank. They are therefore not fit for very light pressures, though they sometimes serve well in the basement of a building where failure would be certain on the upper floor.

Fig. 43. Siphon-Jet Closet with Seat-Operating Pressure Tank.

Courtesy of Crane Company, Chicago

Condensation on single-shell sheet metal tanks is annoying. Open tanks of porcelain and iron are used more or less, but sweating is hard to overcome. Zinc paint and ground cork finishes have been employed with some satisfaction; and drip-cup collars discharging into the flush just under the tank on high-tank closets have served in this capacity, but nothing overcomes the sweating so well as a tight wood case. Insulated metal cases and double enameled cast tank, before mentioned, will prove the only serious rivals to the wood-case tank. Some makes of the pressure-tank closet require too much weight on the seat for successful operation by a child, and children would as a rule leave the seat too soon to allow the tank to fill reasonably well. The after-fill is accomplished by projecting the flush connection into the tank an inch or more, and drilling a hole \ inch or less in diameter through it near the bottom of tank. The rapid flow ceases when the water-level falls to the upper end of the inward-projecting flush connection, and the after-fill drains into the flush.