plan view if the shaft
stands horizontal, but lever B stands also horizontal. We may take the
same drawing and turn it around on the paper as in Figure 143, and it
becomes a side view if the shaft stands vertical, and a plan view if the
shaft stands horizontal and arm D vertical above it.

In a side or an end view, the piece that projects highest in the drawing
is highest when upon the machine; also in a side elevation the piece
that is at the highest point in the drawing extends farthest upward when
the piece is on the machine. But in a plan or top view the height of
vertical pieces is not shown, as appears in the case of arm D in Figure
143.

[Illustration: Fig. 143.]

In either of the levers, Figures 142 or 143, all the dimensions could be
marked if an additional view were given, but this will not be the case
if an eye have a slot in it, as at E, in Figure 144, or a jaw have a
tongue in it, as at F: hence, end views of the eye and the jaw must be
given, which may be most conveniently done by showing them projected
from the ends of those parts as in the figure.

This naturally brings us to a consideration as to the best method of
projecting one view from another. As a general rule, the side elevation
or side view is the most important, because it shows more of the parts
and details of the work; hence it should be drawn first, because it
affords more assistance in drawing the other views.

[Illustration: Fig. 144.]

There are two systems of placing the different views of a piece. In the
first the views are presented as the piece would present itself if it
were laid upon the paper for the side view, and then turned or rolled
upon the paper for the other views, as shown in Figure 145, in which the
piece consists of five sections or members, marked respectively A, B, C,
D, and E. Now if the piece were turned or rolled so that the end face of
B were uppermost, and the member E was beneath, it will, by the
operation of turning it, have assumed the position in the lower view
marked position 2; while if it were turned over upon the paper in the
opposite direction it would assume the position marked 3. This gives to
the mind a clear idea of the various views and positions; but it
possesses some disadvantages: thus, if position 1 is a side elevation or
view of the piece, as it stands when in place of the machine, then E is
naturally the bottom member; but it is shown in the top view of the
drawing, hence what is actually