41. All water-closets within the house must be supplied with water from special tanks or cisterns, the water of which is not used for any other purpose. The closets must never be supplied directly from the Croton supply-pipes. A group of closets may be supplied from one tank; but water-closets on different floors are not permitted to be flushed from one tank. 42. The valves of cisterns must be so fitted and adjusted as to prevent wasting of water, especially where cisterns are supplied from a tank on the roof. 43. The overflow-pipes from water-closet cisterns must discharge into an open sink, or where its discharge will attract attention and indicate that waste of water is occurring, but not into the bowl of the water-closet, not into the soil or waste pipe, nor into the drain or sewer. When the pressure of the Croton is not sufficient to supply these tanks, a pump must be provided. 44. Tanks for drinking-water are objectionable; if indispensable, they must never be lined with lead, galvanized iron, or zinc. They should be constructed of iron, or wood lined with tinned and planished copper. The overflow should discharge upon the roof, or be trapped and discharge into an open sink, never into any soil or waste pipe or water-closet trap, nor into the drain or sewer. 45. Rain-water leaders must never be used as soil, waste, or vent pipes; nor shall any soil, waste, or vent pipe be used as a leader. 46. When within the house, the leader must be of cast-iron, with leaded joints; when outside of the house, and connected with the house-drain, it must be trapped beneath the ground or just inside of the wall, the trap being arranged in either case so as to prevent freezing. In every case where a leader opens near a window or a light-shaft, it must be properly trapped at its base. 47. No steam exhaust or blow-off pipe from a steam-boiler will be allowed to connect with any soil or waste pipe, or directly with the house-drain. They should discharge into a tank or condenser, the waste from which, if to be discharged into the sewer through the house-drain, must be connected on the sewer side of the running trap. 48. Subsoil drains must be provided whenever necessary. 49. Yards and areas should always be properly graded, cemented, flagged, or well paved, and properly drained; when the drain is connected with the house-drain, it must be effectively trapped. Front-area drains must, where practicable, be connected with the house-drain inside of the running trap. 50. Cellar and foundation walls must, where possible, be rendered impervious to dampness, and the use of asphaltum or coal-tar pitch, in addition to hydraulic cement, is recommended for that purpose. 51. No privy-vault or school-sink will be allowed in any cellar or basement; nor shall the general privy accommodation of a tenement or lodging house be allowed to be in the cellar or basement.