ement of, 94-111.

Dimension figures in mechanical drawing, 91.

Dimensions, marking, 91-93.

Distances, relative from the eye, representation of, by line-shading, 89.

Dodecagon, a, 63.

Dotted lines, use of, 48.

Double eye, or knuckle-joint, pencil lines for, 146.
or knuckle-joint, with an offset, 147.

Double thread, 156.

Drawing board, 17, 18.
fastening the drawing to, 278.
size of, 18.
small, advantage of, to student, 18.

Drawing for engraver on wood, 268.
gear wheels, 193-222.

Drawing instruments, 22-26.
parts of, 34.
selecting and testing, 22.

Drawing paper, 26-29.
different qualities, kinds and forms, 26, 27.
location of on the drawing board, 28, 29.

Drawing the curves for screw threads, 159.
to scale, making a, 177.

Drawings for engraving, necessity of conforming to the particular process
of, 266.
for engravings by the wax process, 268, 269.

Drawings for photo-engraving, 266.
for the blacksmith, 172.
shading and coloring, 277-288.

Drilling machine, a boiler, 269, 270.

Eccentric and strap, 301.
to find how much motion it will give to its rod, 223.

Edge view of a wheel, to draw, 203.

Elevation, 94.

Ellipse, dimensions of, how taken and designated, 63.
form of a true, 66.
most correct method of drawing, 72.
the, 63-75.

Elliptical figure, whose proportion of width to breadth shall remain the
same, whatever the length of the major axis, 69.

Emery paper, use of on the lining pen, 37.

Ennagon, a, 62, 63.

Engine work, examples of, 289-303.

Engine, working drawings of a 100 horse-power, 299.

Engravings by the wax process, drawings for, 268, 269.

Examples for practice, 169-177
in bolts, nuts and polygons, 112-151.
of engine work, 289-303.
of work with nine sides, 135.

Feed motion of a Niles horizontal tool work boring mill, 209.

Five-sided figure, to draw, 132, 133.

Flanks of teeth to trace hypocycloides, for, 200.

Foci of an ellipse, 64.

Franklin Institute or United States Standard for heads of bolts and of
nuts, basis of, 118.

Full stroke cam, method of drawing or marking out a, 237-241.

Gear, part of, showing the teeth in, the remainder illustrated by
circles, 209.

Gear teeth, names of the curves and lines of, 193.

Gear wheels, drawing, 193-222.
various examples for laying out, 214-222.

Gearing oval, construction of, 210.

General view, 94.

Geometrical terms, si