A manual of mechanical drawing
A textbook of mechanical drawing by Philip Devereux Johnston, published in New York by D. Williams Company in 1907 for engineering students and draftsmen. The plates are line-engraved orthographic projections — cylinders, cones and machine parts drawn with centre lines, dashed construction rays and hatched sections — supplying geometric diagram vocabulary, technical lettering and dotted-line grids on toned paper.
