One of my favorite artists, Maxfield Parrish was famous for his calendar and children's book illustrations in the first half of the twentieth century. His technique, called glazing, involves layering of translucent colors. Each primary color was thinned with linseed oil and painted one layer at time, not unlike printing. Although many of his paintings are over a hundred years old, the colors have held up well, still vibrant and dream-like.
Maxfield Parrish - Interlude
Maxfield Parrish – Hilltop
Maxfield Parrish -The Knave Of Hearts
For more examples of Parrish's work, try this site: http://americanillustration.org/artists/parrish/parrish.html