Mechanical drawing. Elementary and advanced (1910)
Reid, John S. (John Simpson), 1856- · New York, J. Wiley & sons; [etc, etc.] · leaf 90
in any one of the dihedralangles, and its projections drawn on the corresponding co-ordinate planes. Problems in Descriptive Geometry are usually worked outin the first angle, and nearly all English draftsmen projecttheir drawings in that angle, but in the United States thethird angle is used… … Fig. 107. H.P., Fig. 107, is the Horizontal Plane, V.P. the VerticalPlane, and I.L. the Intersecting Line. The Horizontal Projection of a point is where a perpen-dicular line drawn through the point pierces the H.P. The Vertical Projection of a point is where a per. linedrawn through the point…
