Chap. CXLII.—How to study the Motions of the human Body.
The first requisite towards a perfect acquaintance with the various motions of the human body, is the knowledge of all the parts, particularly the joints, in all the attitudes in which it may be placed. Then make slight sketches in your pocket-book, as opportunities occur, of the actions of men, as they happen to meet your eye, without being perceived by them; because, if they were to observe you, they would be disturbed from that freedom of action, which is prompted by inward feeling; as when two men are quarrelling and angry, each of them seeming to be in the right, and with great vehemence move their eyebrows, arms, and all the other members, using motions appropriated to their words and feelings. This they could not do, if you wanted them to imitate anger, or any other accidental emotion; such as laughter, weeping, pain, admiration, fear, and the like. For that reason, take care never to be without a little book, for the purpose of sketching those various motions, and also groups of people standing by. This will teach you how to compose history. Two things demand the principal attention of a good painter. One is the exact outline and shape of the figure; the other, the true expression of what passes in the mind of that figure, which he must feel, and that is very important.