FARMS 951 
of the seal. With slight modifications this 
is the trap most commonly used for wash 
basins, laundry tubs, etc. Its greatest 
fault is the danger from siphonage; that 
is, the water seal may be carried out of 
the trap into the soil pipe by the rush 
of the water when the fitting itself is 
emptied, by the flow of water from an- 
other fixture on the same branch waste 
pipe, or by the discharge of water from 
a fixture higher up but connected to the 
same soil pipe. This danger is much les- 
sened by the introduction of a system of 
ventilation pipes extending upward either 
from the trap itself or from the outlet 
near the trap. To avoid this extra ex- 
pense of a third system of pipes, it is bet- 
ter to supply each fixture with one of the 
patent non-siphonage traps, which should 
also be self-cleansing. There are several 
good ones on the market. It is a good 
habit, after emptying the wash basin, 
bath tub, or kitchen sink, to allow some 
clean water from the faucet to run into 
the fixture in order to have clean water 
in the traps. All traps should be provid- 
ed with trap screws, placed below the 
water line, and arranged so as to be ac- 
cessible for cleaning. 
Nothing short of continuous use will 
prevent the evaporation of the water in 
the traps. One with a large dip is best, 
but at the same time the trap must be so 
formed that at each use of the fixture all 
the filth that is delivered shall be carried 
away, the trap being immediately refilled 
with fresh water. Hair and fibers from 
cloth sometimes carry the water out of 
traps by capillary attraction, and care 
should be taken not to allow such things 
to enter the pipes. 
The Soil Pipe 
The soil pipe should extend from cellar 
to roof in a straight line, if possible, as 
each offset or bend forms an obstruc- 
tion to its proper flushing with both water 
and air. Use only “extra heavy” soil pipe 
of uniform thickness throughout, as the 
hubs stand the calking better. 
Avoid if possible plumbing fixtures in 
the cellar if the drain must go under the 
floor. If it is necessary to make connec- 
tions with a fixture in the cellar it is bet- 
ter that the main channel should run 
under the floor to or near the location of 
such fixtures that all or nearly all of its 
length should constitute a part of the 
main drain thoroughly flushed and venti- 
lated like the rest of the system. The 
pipe should be laid in an open trench and 
so thoroughly calked that under a pres- 
sure equal to one story in height not a 
drop of water should escape at any point, 
and then it should be inclosed in good con- 
crete, after which the trench should be 
filled. The soil pipe should pass through 
the foundation by means of an arch, and 
the cast iron pipe should extend at least 
5 feet outside the foundation; from there 
on, a carefully laid and rigidly inspected 
vitrified pipe drain is to be preferred. 
The joint between the iron pipe and the 
vitrified sewer pipe should be made with 
neat Portland cement mortar. If there 
are no fixtures in the cellar carry the 
drain in full sight along the face of the 
cellar wall, or suspended from the floor 
beams, so the joints may be inspected. At 
the point where it is to turn up as a ver- 
tical soil pipe support it by a post or a 
brick pier. Use no short turns in the 
soil pipe, like “tees” and “quarter bends.” 
Two one-eighth bends or a Y branch and 
a single one-eighth bend give a more 
gradual and therefore a better change of 
direction. Water closets should connect 
to the soil pipe with a Y branch. The 
soil pipe should be secured along its en- 
tire length at distances not over 5 feet 
with hangers and clamps or hooks, so 
that it will be rigidly held in position. 
The joints in the cast iron soil pipe should 
be made by first inserting a little picked 
oakum into the socket, allowing none to 
enter the pipe; it is better formed into 
a sort of rope. The oakum prevents the 
lead from running into the pipe to form 
an obstruction to the flow. Enough molt- 
en lead is then poured into the hub to fill 
it. After the lead has cooled it is care- 
fully hammered with a special calking 
tool until the space between the spigot 
and the hub is perfectly gas and water 
tight. Every joint should be made with 
a view to being tested with hydraulic 
pressure. 
