The illustrated architectural, engineering, & mechanical drawing-book : for the use of schools, students, and artisans ; upwards of 300 illustrations (1856)
Burn, Robert Scott · London : Ward and Lock, 158 Fleet Street · leaf 129
fig. 20. distance between tliem; the line from g is the line of the inside of thescrew, the line/the outside line of the threads. The last example showsthe method of copying this. ExAMi-LE !iD, fig. 30, represents a helix of wire, ad being centre-line, (^ e being half the thickness of the coil, the…
Architectural drawing · Mechanical drawing
Internet Archive · Public Domain Mark 1.0. Free to use for anything.
