Blessing, George F. (George Frederick), 1875-1921, Darling, Lewis A. (Lewis Andrew) · New York, J. Wiley & sons; [etc., etc.] · leaf 72
,and arrows as used in connection with lettering and numbers,see page 37, § 34. Capital O. 3 strokes. Drawtwo side-guide-lines such thattheir distance apart is equal tothe width of the letter. Bisectthe parallelogram by two centerlines, as shown, and locate thepoints of tangency of the guidelines… … 52 ELEMENTS OF DRAWING Capital Q. 4 strokes. Threestrokes, as for 0. (See page 51.)#4 is drawn very lightly from theleft-hand point of tangency to theintersection of the right-hand andbottom guide lines. Erase abouttwo-thirds of the left-hand portionof this line and retrace the remain-ing portion…
Mechanical drawing
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
![An illustration from L'optique divisée en trois livres : ou, l'On démontre d'une maniere aisée tout ce qui regarde 1. la propagation & les proprietez de la lumiere. 2. La vision. 3. La figure & la disposition des verres qui servent à la perfefectionner [sic] (1682)](https://img.insideoutlibrary.com/img/200/ia-loptiquedivise00ango-318-34.webp)
![An illustration from [Electric engineering.] (1902)](https://img.insideoutlibrary.com/img/200/ia-electricengineer01inte-394-153.webp)
