Andrew Loomis was an American illustrator whose work appeared in many magazines in the mid-20th century. In addition to his beautiful editorial work for magazines, Loomis also wrote and illustrated a half dozen or so instructional drawing books, and for the last 30 years or so they've been in great demand, even though they've been out of print.
The most recent Loomis reprint is called Successful Drawing. Even though it's probably my least favorite of the three Loomis titles reprinted so far, the lessons on shading, perspective, and proportion are much better than most contemporary instructional art books.
More images after the jump.