Now six months have passed which have been entirely devoted to drawing . . . I have attached great value to drawing and will continue to, because it is the backbone of painting, the skeleton that supports all the rest.
Let no day pass over you without a line. Observe as you walk the streets, the airs of heads; the natural posturs and expressions; which are always the most free the less they seem to be observ'd. Be ready to put into your table-book (which you must always carry about you) whatsoever you judge worthy of it; whether it be upon the earth, or in the air, or upon the waters, while the species of them is yet fresh in your imagination.