The water-heating tanks for the three systems are nested as shown in Fig. 7. They are each heated by exhaust steam through the 7-inch pipe A, which connects to each tank by the two 3-inch pipes B B with stop valves close to the tanks. Each of the pipes B B is connected to the 4 inch brass tube return coil heater C, shown through the broken shell of tank D,

Fig.6.

The exhaust steam enters at both ends of the coil C, acting as a surface condenser and without circulation, the waste passing off to cesspool through the pipe H and the valve I. Should it be necessary to heat the water by live steam, the valves E are closed and the valves F on the live-steam pipe G are opened. Valve I is closed and the valve J is opened, allowing the condensation to pass to the trap K and on to the pump through the pipe L.

Cold water is laid on to the tank D from the upper system cold-water tank, through the 2-inch pipe M, and the hot water for the same system leaves the tank through the pipe N. The pipes O and P serve in like manner the intermediate system and tank Q, while the pipes R and S serve lower system and tank T. To guard against excessive pressure each tank was provided with the safety valves U, the wastes of which empty into the storage tanks. The valves V are for emptying the tanks.

The cold water for the upper and intermediate sys-tems is pumped to the respective tanks by two I2*x 6"x 10" Worthington duplex pumps. The 4-inch pipe A, Fig 8, is for fire service, the 2-inch pipe B is to the tanks on the seventeenth floor, and the 3-inch pipe C is to the tanks on the ninth and tenth floors.

P'ART IV. - DETAILS OF ROOF TANKS AND INTERMEDIATE TANKS AND CONNECTIONS.

Figure 9 is a diagram of the arrangement of the roof tanks conventionally shown in Fig. 3. They are filled through a 3-inch pump pipe M, and are connected by an open equalizing pipe A.

Figure 10 is a side elevation of one of the tanks, and Fig. 11 is an elevation at Z Z, Fig. 10. The tanks each rest on four 12 inch rolled steel beams D D, etc., which are supported at a convenient height above the floor by I-beam pillars E E, etc., which are set on the iron floor girders below. These pillars, as well as all pipes that pass through the roof, are cased with copper flashings G G, etc., which have horizontal flanges H H, etc., resting directly upon the brickwork and covered by the cement surface I I. The pipes are also provided with sleeves L L and bottom escutcheons.

The water supply from pump main M is controlled by valve B and received in stand pipe C. Delivery is through pipe O to the hot-water boiler in the basement, through N to the house service main for the upper system, and through Q to the five mains. At k is represented a ½-inch pressure pipe to the engine-room gauge. J is a vent and K is an expansion pipe, T is a telltale to a sink in the engine-room. P P are a row of ¾-inch air pipes from different riser lines. There is a 4-inch overflow f emptying on the roof. S S are angle braces for the supporting beams.

Figure 12 shows the connections of the two 3,500-gallon tanks on the ninth and tenth floors for supplying the intermediate system. Water is received through the 2-inch pump pipe L. which is sleeved to prevent noise and splashing, and immediately fills the lower tank through the 2-inch pipe d, and five 1-inch ball cocks, which close when the lower tank is full and permit the upper tank to fill up to the level of its 3-inch overflow/". This overflow empties into the lower tank and causes it to overflow through the 4-inch galvanized-iron emptying pipe P; at the same time indicating the fact by a discharge of water through the small telltale pipe /, the discharge of which is visible in a sink in the engine-room. At j is a pressure pipe to a gauge in the engine-room which indicates the height of water in the upper tank; h h are safe wastes. P is an emptying pipe to the sewer. M is a 3-inch supply to the cold-water distribution system in the cellar. N is a 3-inch supply to the hot-water boiler of the intermediate system. At J there are 36 ½-inch vent pipes from rising lines of the intermediate system.

Fig.9.