A book about drawing

The Practice and Science of Drawing
Here you see some drawings by the author, Harold Speed who was born in 1872, was an English Royal Academician, and lived until 1957. That's my high school girlfriend on the right.
If you go to a bookstore there are shelves full of books on drawing, but this small volume is, in my opinion the best book on the subject. You can get the entire book as a PDF file from the Gutenberg Foundation for free!
The problem with most art books is that the author is himself not an expert. You leaf through most books on drawing and say to yourself, "I can draw that well". You won't feel that way looking at Harold Speeds drawings, he was a consummate draftsman and could explain what he did, how and why.
I have a theory,

NO ONE CAN TEACH YOU TO DO ANYTHING IN ART, THAT THEY CAN'T DO THEMSELVES!

I know that sounds a little over the top, but I do like to be provocative you know. That kind of thinking ended my art school experience.
I know of no one alive today I would consider a better draftsman than Harold Speed. The drawing skill that was common among the academy trained artists of the 19th century is very rare today.
Speed uses reproductions of his own drawings and those of the masters to present an orderly and worksmanlike method of drawing both accurately and expressively. One of the all time great texts and yours free for the taking.
Copy and paste the URL below into your browser and there you are :

http://cg2020.com/docs/TheProjectGutenbergeBookofThePracticeAndScienceOfDrawing.pdf