A textbook on mechanical and electrical engineering (1902)
International Correspondence Schools · Scranton : International Textbook Co. · leaf 260
view of theobject of which the projection draAving is a representation,the eye of the observer is ahvays supposed to be directlyover or opposite that point in the drawing which is beingnoted. §15 PRACTICAL PROJECTION This may be illustrated by the student for himself in avery simple way. Place a… … Fig. 1 to correspond with the divisions on the rule. He will findthat he is obliged to get his eye directly over each mark onthe rule, and to sight carefully down on to the rulebefore making each mark, very much as he would sightor look along a piece of work to see whether it is straight ornot. It…
