An Online Ink-Drawing Book
This was just released by the Gutenberg Project, an entire 19th century pen and ink manual.
Pen Drawing, an illustrated treatise, byCharles Maginnis
UPDATE: Here's another one. The Practice and Science of Drawing, By Harold Speed.
Pen Drawing, an illustrated treatise, byCharles Maginnis
UPDATE: Here's another one. The Practice and Science of Drawing, By Harold Speed.