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Rh "left end elevation," depending upon whether the view is that of the right end or the left end. At E is shown the bottom view, which would be that obtained by looking up from beneath in the direction of the arrow, Z. These views are not all needed to show the complete shape of the anvil. They are, however, all the different views that might be used by the draftsman. These "views" are also called the "projections" of the object, and this method of showing it is called "projection."

Drawings are made in the drafting room and are then sent to the shop so that the object shown can be made. Consequently, all drawings must have complete information on them so that no questions need be asked. Besides showing the shape and size of

the parts, the drawings must have full information as to the material to be used, its gage, number wanted, etc.

3. Drawing Instruments.—The Drawing Board and T-Square.—The drawing board. Fig. 3, is for the purpose of holding the paper while the drawing is being made. It is usually made of some soft wood, free from knots and cracks and provided with cleats across the back or ends.

The T-square, Fig. 4, consists of a head and blade fastened together at right angles. The upper or working edge of the blade is used for drawing all horizontal lines (lines running the long way of the board) and must be straight.

The left end of the drawing board must also be straight. The working edge of the T-square and the working edge of the drawing