"These divisions consist of the head, with its features taken in three points of view, front, back, and profile; the neck in like manner, also the thorax, abdomen, and pelvis; thigh, knee, leg, ankle, the carpus, metacarpus, and toes; the clavicula, arm, fore-arm, wrist, carpus, metacarpus, and fingers. While you are employed on these, it would be highly proper to have before you the osteology of the part on which you are engaged, as in that consists the foundation of your pursuit. And, in this period of your studies, I recommend that your drawings be geometrical, as when you draw and study a column with its base and capital. At the same time you should not neglect to gain a few points in perspective, particularly so far as to give effect to the square and cylinder, in order to know what constitutes the vanishing point, and point of distance, in the subject you are going to draw.
"After you have perfected yourselves in the parts of the figure, begin to draw the Greek figures entire, with the same attention to correctness as when you drew the divisions in your earlier lessons. Attend to the perspective according to the vanishing point opposite to your eye. You will naturally seek to possess your mind with the special character of the figure before you;--and of all the Grecian figures, I would advise you to make from the Apollo and Venus a general measurement or standard for man and woman, taking the head and its features, as the part by which you measure the divisions of those figures.
"Light and shade must not be neglected; for what you effect in drawing by the contour of the figure, light and shade must effect with the projections of those parts which front you in the figure. Light and shade there produce what becomes outline to another drawing of the same object in a right angle to the place where you sit.
"It seems not impossible to reduce to the simplicity of rule or principle, what may have appeared difficult in this branch of art to young students, and may have been too often pursued at random by others. All forms in nature, both animate and inanimate, partake of the round form more than of any other shape; and when lighted, whether by the sun or flame, or by apertures admitting light, must have two relative extremes of light and shadow, two balancing tints, the illuminated and the reflected, divided by a middle tint or the aerial. The effect of illumination by flame or aperture, differs from that of the sun in this respect; the sun illuminates with parallel rays, which fall over all parts of the enlightened side of the subject, while the light of a flame or an aperture only strikes directly on the nearest point of the object, producing an effect which more or less resembles the illumination of the sun in proportion to the distance and dimensions of the object.
"Let us then suppose a ball to be the object on which the light falls, in a direction of forty-five degrees or the diagonal of a square, and at a right angle from the ball to the place where you stand. One half of the ball will appear illuminated, and the other dark. This state of the two hemispheres constitutes the two masses of light and shadow. In the centre of the mass of light falls the focus of the illumination in the ball; between the centre of the illumination and the circle of the ball, where the illumination, reaches its extremity, lies what may be called the transparent tint; and between it and the dark side of the ball lies the serial or middle tint. The point of darkness, the extreme of shade, is diametrically opposite to the focus of illumination, between which and the aerial tint lies the tint of reflection. If the ball rests on a plain, it will throw a shadow equal in length to one diameter and a quarter of the ball. That shadow will be darker than the shade on the ball, and the darkest part will be where the plain and ball come in contact with each other.
"This simple experiment, whether performed in the open sun-shine, or with artificial illumination, will lead you to the true principles of light and shade over all objects in nature, whether mountains, clouds, rocks, trees, single figures, or groups of figures. It would therefore be of great use, when you are going to give light and shade to any object, first to make the experiment of the ball, and in giving that light and shade, follow the lessons with which it will furnish you.
"You will find that this experiment will instruct you, not only in the principles of light and shade, but also of colours; for that there is a corresponding hue with respect to colours is not to be disputed. In order to demonstrate this, place in the ball which you have illuminated, the prismatic colours, suiting their hues to those of the tints. Yellow will answer to the focus of illumination, and the other secondary and primary hues will fall into their proper places. Hence, on the enlightened side of a group or figure, you may lay yellow, orange, red, and then violet, but never on the side where the light recedes. On that side must come the other prismatic colours in their natural order. Yellow must pass to green, the green to blue, and the blue to purple. The primary colours of yellow, orange, and red, are the warm colours, and belong to the illuminated side of objects; the violet is the intermediate, and green, blue, and purple are the cold colours, and belong to the retiring parts of your composition.
"On the same principle, and in the same order, must be placed the tints which compose the fleshy bodies of men and women, but so blended with each other, as to give the softness appropriate to the luminous quality and texture of flesh; paying attention, at the same time, to reflections on its surface from other objects, and to its participation of their colours. The latter is a distinct circumstance arising from accident.
"When the sun illuminates a human body, in the same manner as the ball, the focus of the illumination in that body will partake of the yellow; and the luminous or transparent tint, will have the orange and the red. These produce, what is called, the carnation. The pure red, occasioned by the blood, lies in the lips, cheeks, joints, and extremities of the figure, and no where else. On the receding side of the focus is the local colour of the flesh, and on the receding side of that is the greenish tint; in the shade will fall the cold or bluish, and in the reflection will fall the tint of purple. The most perfect tint of ground, from which to relieve this arrangement of colours, is either blue, grey, or purple, for those colours partake of the complexion of the watery sky in which the rainbow appears, or the ground which best exhibits the prismatic colours.
"In acquiring a practical knowledge of the happiest manner of distributing your colours according to nature, it will assist you, if you will copy with attention some pieces of Titian, Correggio, Reubens, and Vandyke; the masters in whose works you will most eminently find the system pursued, which I have endeavoured to illustrate by the simple image of the ball.