Notes on mechanical drawing;
Notes on Mechanical Drawing is a 1912 drafting textbook by Horace Pugh Fry, published in Philadelphia by John C. Winston for engineering and trade-school students learning drawing-board practice. Its 49 plates are hairline ink diagrams: hatched screw-thread sections with pitch and depth dimensions, helix constructions plotted from a divided circle, and multi-view projections labeled with numbered and lettered reference points, useful as ready-made technical line work, arrowed dimension lines, and diagonal section hatching.
