The low-down water closet appears to be displacing the high-tank water closet to a large extent. Some of the advantages of this style of water closet are, viz.: the flush tank is more accessible, and, being covered, prevents dust, dirt, etc., from entering the tank and doing harm to the valves; and, because of the small elevation required, it may be used in many places where the high tank could not be used.
Plate V. The Low-Down Water Closet - Flush Valves - Water Closet Ranges
Plate 5. Connections for Low-Down Water Closet
Water Closet Operatect by Flushing Valve.
The low-down tank, however, requires the setting of the water closet further out into the room.
With the exception of the differences in the flushing arrangement, the principles that apply to the high-tank water closet also apply to the low-down style.
The flush of the low-down water closet as it enters the bowl has very little head, while in the case of the high tank it has a head due to an elevation of 6 ft. This lack is made up by providing a much larger flush pipe, in order that a large volume of water may enter the bowl with sufficient rapidity to produce siphonage. A water closet of the siphon pattern should be used in connection with the low-down tank, as enough water cannot enter to produce good results except by siphonage.