This section is from the book "American Plumbing Practice", by The Engineering Record. Also available from Amazon: Plumbing: A working manual of American plumbing practice.
Figure 7 is a view of the basement battery of three hot-water boilers AAA, each of which is about 4 feet diameter by 10 feet long. B is a live and C an exhaust pipe, from either of which each boiler can receive steam through its branch D, which connects with a 200-foot interior coil of 1½-inch brass pipe, whose drip, etc. discharge through branches E E E. and return main F. Cold water under street and tank pressure respectively is supplied through 2-inch pipe G and 4-inch pipe H, and the 1½-inch branches I and 2-inch branches J. Hot water is delivered at M M M, and is admitted to the 4-inch tank pressure main K, or the 2 inch street pressure main L, according to whether that boiler is supplied with cold, street or tank water. N is a 2-incb circulation pipe, with 1½-inch branches O O O to each boiler. P P P are safety valves, and Q Q Q are check valves, closing with a current away from the boiler, so as to prevent possible escape of tank water into the street mains. R is an emptying pipe from rising lines to the sewer.
In the public toilet-room a group of five urinals automatically flushed by one cistern, arranged as shown in Fig. 8, the header B being designed to have a capacity in excess of the combined draft of all the branches B B, etc. to each bowl. A grated floor drainer S is set under every urinal and its ventilation, together with that of the trap and the bowl, is shown in Fig. 9, where full arrows indicate the directions of air currents and dotted arrows indicate that of the waste. Galvanized-iron duct V connects with a vertical conduit extending through a light shaft to above the roof, and containing at the bottom 32 gas flames to promote the circulation. Figure 10 shows the arrangement of all the hot and cold-water risers which supply the different lines of fixtures throughout the house. Immediately above the distribution main C an air chamber D is branched off from the riser A, which is continued above the supply B, of the highest story, to form a second air chamber E. Beside this an air chamber is provided at every fixture. F F are petcocks.