sketch of a dwelling, and if they were to be actually
put in, they would fit. The reader would do well to copy this
sketch and follow the piping and check the measurements according
to the plan, and note how the different risers, drops, etc., are
drawn. It is not necessary in a sketch of this kind to draw to a
scale. After the different measurements are the letters _C.C._,
_E.C._, _E.E._, _C.B._ and _E.B._, meaning center to center, end to
center, end to end, center to back, and end to back, respectively.
Offsetting pipe is a very convenient way of getting the pipe or
fittings back to the wall for support. To offset pipe properly and
with little trouble, take a piece of scantling 2 by 4 and brace it
between the floor and ceiling. Bore a few different-sized holes
through it and you will have a very handy device for offsetting
pipe. There is a little trick in offsetting pipe that one will have
to practice to obtain. The pipe must be held firmly in the place
where the pipe is to be bent. Large offsets and bends should not be
made; 2 to 4 inches is as large as should be used. Larger offsets
that are required should be made with fittings. Always make the
offsets true and have the ends perfectly straight. Before putting a
piece of pipe permanently in place, always look or blow through it,
to ascertain if its bore is obstructed or not. Sometimes dirt or
slag will collect and cause stoppage.

READING THE PIPE SKETCH.--Vertical lines represent vertical pipes
(see Fig. 81). Horizontal lines represent horizontal pipes running
parallel to the front. Diagonal lines represent horizontal pipes
running from back to front. Any line that is drawn perpendicular to
any other line stands for a horizontal pipe. A diagonal line
separating a vertical line or horizontal line or set of lines
represents a different horizontal plane. With this explanation the
sketch will be made clear to one after drawing it. The reader
should now take each measurement and check it on the plan. This is
easily done by using a scale rule. The height of the ceiling is
8-1/2 feet on the first floor, the second floor is 8 feet. The
first floor joists are 10 inches, the second floor joists are 9
inches. An outlet is indicated by a small circle. In the piping
sketch, this circle is connected with the riser or drop by a
horizontal line. At the junction of these two lines a short
perpendicular line is drawn, and indicates the direction of the
outlet.

Let me again emph