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A Treatise on Painting

Chapter 224: REFLEXES.
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About This Book

The work gathers practical and theoretical guidance on painting, covering drawing, proportion, and anatomical study; the motion and equilibrium of figures; rules of linear perspective; methods of composition and invention; and the depiction of expression, drapery, light, and shadow. It stresses learning from nature through careful observation, measurement, and memory, and explains joints, muscles, and weight distribution to render believable poses and gestures. Technical precepts are paired with illustrative plates and systematic chapters intended to instruct students and inform the practices of working painters.

Chap. CLXXXIII.Of the best Light.

The light from on high, and not too powerful, will be found the best calculated to shew the parts to advantage.

Chap. CLXXXIV.Of Drawing by Candle-light.

To this artificial light apply a paper blind, and you will see the shadows undetermined and soft.

Chap. CLXXXV.Of those Painters who draw at Home from one Light, and afterwards adapt their Studies to another Situation in the Country, and a different Light.

It is a great error in some painters who draw a figure from Nature at home, by any particular light, and afterwards make use of that drawing in a picture representing an open country, which receives the general light of the sky, where the surrounding air gives light on all sides. This painter would put dark shadows, where Nature would either produce none, or, if any, so very faint as to be almost imperceptible; and he would throw reflected lights where it is impossible there should be any.

Chap. CLXXXVI.How high the Light should be in drawing from Nature.

To paint well from Nature, your window should be to the North, that the lights may not vary. If it be to the South, you must have paper blinds, that the sun, in going round, may not alter the shadows. The situation of the light should be such as to produce upon the ground a shadow from your model as long as that is high.

Chap. CLXXXVII.What Light the Painter must make use of to give most Relief to his Figures.

The figures which receive a particular light shew more relief than those which receive an universal one; because the particular light occasions some reflexes, which proceed from the light of one object upon the shadows of another, and helps to detach it from the dark ground. But a figure placed in front of a dark and large space, and receiving a particular light, can receive no reflexion from any other objects, and nothing is seen of the figure but what the light strikes on, the rest being blended and lost in the darkness of the back ground. This is to be applied only to the imitation of night subjects with very little light.

Chap. CLXXXVIII.Advice to Painters.

Be very careful, in painting, to observe, that between the shadows there are other shadows, almost imperceptible, both for darkness and shape; and this is proved by the third proposition [38], which says, that the surfaces of globular or convex bodies have as great a variety of lights and shadows as the bodies that surround them have.

Chap. CLXXXIX.Of Shadows.

Those shadows which in Nature are undetermined, and the extremities of which can hardly be perceived, are to be copied in your painting in the same manner, never to be precisely finished, but left confused and blended. This apparent neglect will shew great judgment, and be the ingenious result of your observation of Nature.

Chap. CXC.Of the Kind of Light proper for drawing from Relievos, or from Nature.

Lights separated from the shadows with too much precision, have a very bad effect. In order, therefore, to avoid this inconvenience, if the object be in the open country, you need not let your figures be illumined by the sun; but may suppose some transparent clouds interposed, so that the sun not being visible, the termination of the shadows will be also imperceptible and soft.

Chap. CXCI.Whether the Light should be admitted in Front or sideways; and which is most pleasing and graceful.

The light admitted in front of heads situated opposite to side walls that are dark, will cause them to have great relievo, particularly if the light be placed high; and the reason is, that the most prominent parts of those faces are illumined by the general light striking them in front, which light produces very faint shadows on the part where it strikes; but as it turns towards the sides, it begins to participate of the dark shadows of the room, which grow darker in proportion as it sinks into them. Besides, when the light comes from on high, it does not strike on every part of the face alike, but one part produces great shadows upon another; as the eyebrows, which deprive the whole sockets of the eyes of light. The nose keeps it off from great part of the mouth, and the chin from the neck, and such other parts. This, by concentrating the light upon the most projecting parts, produces a very great relief.

Chap. CXCII.Of the Difference of Lights according to the Situation.

A small light will cast large and determined shadows upon the surrounding bodies. A large light, on the contrary, will cast small shadows on them, and they will be much confused in their termination. When a small but strong light is surrounded by a broad but weaker light, the latter will appear like a demi-tint to the other, as the sky round the sun. And the bodies which receive the light from the one, will serve as demi-tints to those which receive the light from the other.

Chap. CXCIII.How to distribute the Light on Figures.

The lights are to be distributed according to the natural situation you mean your figures should occupy. If you suppose them in sunshine, the shades must be dark, the lights broad and extended, and the shadows of all the surrounding objects distinctly marked upon the ground. If seen in a gloomy day, there will be very little difference between the lights and shades, and no shadows at the feet. If the figures be represented within doors, the lights and shadows will again be distinctly divided, and produce shadows on the ground. But if you suppose a paper blind at the window, and the walls painted white, the effect will be the same as in a gloomy day, when the lights and shadows have little difference. If the figures are enlightened by the fire, the lights must be red and powerful, the shadows dark, and the shadows upon the ground and upon the walls must be precise; observing that they spread wider as they go off from the body. If the figures be enlightened, partly by the sky and partly by the fire, that side which receives the light from the sky will be the brightest, and on the other side it will be reddish, somewhat of the colour of the fire. Above all, contrive, that your figures receive a broad light, and that from above; particularly in portraits, because the people we see in the street receive all the light from above; and it is curious to observe, that there is not a face ever so well known amongst your acquaintance, but would be recognised with difficulty, if it were enlightened from beneath.

Chap. CXCIV.Of the Beauty of Faces.

You must not mark any muscles with hardness of line, but let the soft light glide upon them, and terminate imperceptibly in delightful shadows: from this will arise grace and beauty to the face.

Chap. CXCV.How, in drawing a Face, to give it Grace, by the Management of Light and Shade.

A face placed in the dark part of a room, acquires great additional grace by means of light and shadow. The shadowed part of the face blends with the darkness of the ground, and the light part receives an increase of brightness from the open air, the shadows on this side becoming almost insensible; and from this augmentation of light and shadow, the face has much relief, and acquires great beauty.

Chap. CXCVI.How to give Grace and Relief to Faces.

In streets running towards the west, when the sun is in the meridian, and the walls on each side so high that they cast no reflexions on that side of the bodies which is in shade, and the sky is not too bright, we find the most advantageous situation for giving relief and grace to figures, particularly to faces; because both sides of the face will participate of the shadows of the walls. The sides of the nose and the face towards the west, will be light, and the man whom we suppose placed at the entrance, and in the middle of the street, will see all the parts of that face, which are before him, perfectly illumined, while both sides of it, towards the walls, will be in shadow. What gives additional grace is, that these shades do not appear cutting, hard, or dry, but softly blended and lost in each other. The reason of it is, that the light which is spread all over in the air, strikes also the pavement of the street, and reflecting upon the shady part of the face, it tinges that slightly with the same hue: while the great light which comes from above being confined by the tops of houses, strikes on the face from different points, almost to the very beginning of the shadows under the projecting parts of the face. It diminishes by degrees the strength of them, increasing the light till it comes upon the chin, where it terminates, and loses itself, blending softly into the shades on all sides. For instance, if such light were A E, the line F E would give light even to the bottom of the nose. The line C F will give light only to the under lip; but the line A H would extend the shadow to all the under parts of the face, and under the chin.

In this situation the nose receives a very strong light from all the points A B C D E.

Chap. CXCVII.Of the Termination of Bodies upon each other.

When a body, of a cylindrical or convex surface, terminates upon another body of the same colour, it will appear darker on the edge, than the body upon which it terminates. And any flat body, adjacent to a white surface, will appear very dark; but upon a dark ground it will appear lighter than any other part, though the lights be equal.

Chap. CXCVIII.Of the Back-grounds of painted Objects.

The ground which surrounds the figures in any painting, ought to be darker than the light part of those figures, and lighter than the shadowed part.

Chap. CXCIX.How to detach and bring forward Figures out of their Back-ground.

If your figure be dark, place it on a light ground; if it be light, upon a dark ground; and if it be partly light and partly dark, as is generally the case, contrive that the dark part of the figure be upon the light part of the ground, and the light side of it against the dark [39].

Chap. CC.Of proper Back-grounds.

It is of the greatest importance to consider well the nature of back-grounds, upon which any opake body is to be placed. In order to detach it properly, you should place the light part of such opake body against the dark part of the back-ground, and the dark parts on a light ground[40]; as in the cut [41].

Chap. CCI.Of the general Light diffused over Figures.

In compositions of many figures and animals, observe, that the parts of these different objects ought to be darker in proportion as they are lower, and as they are nearer the middle of the groups, though they are all of an uniform colour. This is necessary, because a smaller portion of the sky (from which all bodies are illuminated) can give light to the lower spaces between these different figures, than to the upper parts of the spaces. It is proved thus: A B C D is that portion of the sky which gives light to all the objects beneath; M and N are the bodies which occupy the space S T R H, in which it is evidently perceived, that the point F, receiving the light only from the portion of the sky C D, has a smaller quantity of it than the point E which receives it from the whole space A B (a larger portion than C D); therefore it will be lighter in E than in F.

Chap. CCII.Of those Parts in Shadows which appear the darkest at a Distance.

The neck, or any other part which is raised straight upwards, and has a projection over it, will be darker than the perpendicular front of that projection; and this projecting part will be lighter, in proportion as it presents a larger surface to the light. For instance, the recess A receives no light from any part of the sky G K, but B begins to receive the light from the part of the sky H K, and C from G K; and the point D receives the whole of F K. Therefore the chest will be as light as the forehead, nose, and chin. But what I have particularly to recommend, in regard to faces, is, that you observe well those different qualities of shades which are lost at different distances (while there remain only the first and principal spots or strokes of shades, such as those of the sockets of the eyes, and other similar recesses, which are always dark), and at last the whole face becomes obscured; because the greatest lights (being small in proportion to the demi-tints) are lost. The quality, therefore, and quantity of the principal lights and shades are by means of great distance blended together into a general half-tint; and this is the reason why trees and other objects are found to be in appearance darker at some distance than they are in reality, when nearer to the eye. But then the air, which interposes between the objects and the eye, will render them light again by tinging them with azure, rather in the shades than in the lights; for the lights will preserve the truth of the different colours much longer.

Chap. CCIII.Of the Eye viewing the Folds of Draperies surrounding a Figure.

The shadows between the folds of a drapery surrounding the parts of the human body will be darker as the deep hollows where the shadows are generated are more directly opposite the eye. This is to be observed only when the eye is placed between the light and the shady part of the figure.

Chap. CCIV.Of the Relief of Figures remote from the Eye.

Any opake body appears less relieved in proportion as it is farther distant from the eye; because the air, interposed between the eye and such body, being lighter than the shadow of it, it tarnishes and weakens that shadow, lessens its power, and consequently lessens also its relief.

Chap. CCV.Of Outlines of Objects on the Side towards the Light.

The extremities of any object on the side which receives the light, will appear darker if upon a lighter ground, and lighter if seen upon a darker ground. But if such body be flat, and seen upon a ground equal in point of light with itself, and of the same colour, such boundaries, or outlines, will be entirely lost to the sight [42].

Chap. CCVI.How to make Objects detach from their Ground, that is to say, from the Surface on which they are painted.

Objects contrasted with a light ground will appear much more detached than those which are placed against a dark one. The reason is, that if you wish to give relief to your figures, you will make those parts which are the farthest from the light, participate the least of it; therefore they will remain the darkest, and every distinction of outline would be lost in the general mass of shadows. But to give it grace, roundness, and effect, those dark shades are always attended by reflexes, or else they would either cut too hard upon the ground, or stick to it, by the similarity of shade, and relieve the less as the ground is darker; for at some distance nothing would be seen but the light parts, therefore your figures would appear mutilated of all that remains lost in the back-ground.


CONTRASTE AND EFFECT.

Chap. CCVII.A Precept.

Figures will have more grace, placed in the open and general light, than in any particular or small one; because the powerful and extended light will surround and embrace the objects: and works done in that kind of light appear pleasant and graceful when placed at a distance[43], while those which are drawn in a narrow light, will receive great force of shadow, but will never appear at a great distance, but as painted objects.

Chap. CCVIII.Of the Interposition of transparent Bodies between the Eye and the Object.

The greater the transparent interposition is between the eye and the object, the more the colour of that object will participate of, or be changed into that of the transparent medium [44].

When an opake body is situated between the eye and the luminary, so that the central line of the one passes also through the centre of the other, that object will be entirely deprived of light.

Chap. CCIX.Of proper Back-grounds for Figures.

As we find by experience, that all bodies are surrounded by lights and shadows, I would have the painter to accommodate that part which is enlightened, so as to terminate upon something dark; and to manage the dark parts so that they may terminate on a light ground. This will be of great assistance in detaching and bringing out his figures[45].

Chap. CCX.Of Back-grounds.

To give a great effect to figures, you must oppose to a light one a dark ground, and to a dark figure a light ground, contrasting white with black, and black with white. In general, all contraries give a particular force and brilliancy of effect by their opposition[46].


REFLEXES.

Chap. CCXI.Of Objects placed on a light Ground, and why such a Practice is useful in Painting.

When a darkish body terminates upon a light ground, it will appear detached from that ground; because all opake bodies of a curved surface are not only dark on that side which receives no light, and consequently very different from the ground; but even that side of the curved surface which is enlightened, will not carry its principal light to the extremities, but have between the ground and the principal light a certain demi-tint, darker than either the ground or that light.

Chap. CCXII.Of the different Effects of White, according to the Difference of Back-grounds.

Any thing white will appear whiter, by being opposed to a dark ground; and, on the contrary, darker upon a light ground. This we learn from observing snow as it falls; while it is descending it appears darker against the sky, than when we see it against an open window, which (owing to the darkness of the inside of the house) makes it appear very white. Observe also, that snow appears to fall very quick and in a great quantity when near the eye; but when at some distance, it seems to come down slowly, and in a smaller quantity [47].

Chap. CCXIII.Of Reverberation.

Reverberations are produced by all bodies of a bright nature, that have a smooth and tolerably hard surface, which, repelling the light it receives, makes it rebound like a foot-ball against the first object opposed to it.

Chap. CCXIV.Where there cannot be any Reverberation of Light.

The surfaces of hard bodies are surrounded by various qualities of light and shadow. The lights are of two sorts; one is called original, the other derivative. The original light is that which comes from the sun, or the brightness of fire, or else from the air. The derivative is a reflected light. But to return to our definition, I say, there can be no reflexion on that side which is turned towards any dark body; such as roofs, either high or low, shrubs, grass, wood, either dry or green; because, though every individual part of those objects be turned towards the original light, and struck by it; yet the quantity of shadow which every one of these parts produces upon the others, is so great, that, upon the whole, the light, not forming a compact mass, loses its effect, so that those objects cannot reflect any light upon the opposite bodies.

Chap. CCXV.In what Part the Reflexes have more or less Brightness.

The reflected lights will be more or less apparent or bright, in proportion as they are seen against a darker or fainter ground; because if the ground be darker than the reflex, then this reflex will appear stronger on account of the great difference of colour. But, on the contrary, if this reflexion has behind it a ground lighter than itself, it will appear dark, in comparison to the brightness which is close to it, and therefore it will be hardly perceptible [48].

Chap. CCXVI.Of the reflected Lights which surround the Shadows.

The reflected lights which strike upon the midst of shadows, will brighten up or lessen their obscurity in proportion to the strength of those lights, and their proximity to those shadows. Many painters neglect this observation, while others attend to and deduce their practice from it. This difference of opinion and practice divides the sentiments of artists, so that they blame each other for not thinking and acting as they themselves do. The best way is to steer a middle course, and not to admit of any reflected light, but when the cause of it is evident to every eye; and vice versâ, if you introduce none at all, let it appear evident that there was no reasonable cause for it. In doing so, you will neither be totally blamed nor praised by the variety of opinion, which, if not proceeding from entire ignorance, will ensure to you the approbation of both parties.

Chap. CCXVII.Where Reflexes are to be most apparent.

Of all reflected lights, that is to be the most apparent, bold, and precise, which detaches from the darkest ground; and, on the contrary, that which is upon a lighter ground will be less apparent. And this proceeds from the contraste of shades, by which the faintest makes the dark ones appear still darker; so in contrasted lights, the brightest cause the others to appear less bright than they really are[49].

Chap. CCXVIII.What Part of a Reflex is to be the lightest.

That part will be the brightest which receives the reflected light between angles the most nearly equal. For example, let N be the luminary, and A B the illuminated part of the object, reflecting the light over all the shady part of the concavity opposite to it. The light which reflects upon F will be placed between equal angles. But E at the base will not be reflected by equal angles, as it is evident that the angle E A B is more obtuse than the angle E B A. The angle A F B however, though it is between angles of less quality than the angle E, and has a common base B A, is between angles more nearly equal than E, therefore it will be lighter in F than in E; and it will also be brighter, because it is nearer to the part which gives them light. According to the 6th rule [50], which says, that part of the body is to be the lightest, which is nearest to the luminary.

Chap. CCXIX.Of the Termination of Reflexes on their Grounds.

The termination of a reflected light on a ground lighter than that reflex, will not be perceivable; but if such a reflex terminates upon a ground darker than itself, it will be plainly seen; and the more so in proportion as that ground is darker, and vice versa[51].

Chap. CCXX.Of double and treble Reflexions of Light.

Double reflexes are stronger than single ones, and the shadows which interpose between the common light and these reflexes are very faint. For instance, let A be the luminous body, A N, A S, are the direct rays, and S N the parts which receive the light from them. O and E are the places enlightened by the reflexion of that light in those parts. A N E is a single reflex, but A N O, A S O is the double reflex. The single reflex is that which proceeds from a single light, but the double reflexion is produced by two different lights. The single one E is produced by the light striking on B D, while the double one O proceeds from the enlightened bodies B D and D R co-operating together; and the shadows which are between N O and S O will be very faint.

Chap. CCXXI.Reflexes in the Water, and particularly those of the Air.

The only portion of air that will be seen reflected in the water, will be that which is reflected by the surface of the water to the eye between equal angles; that is to say, the angle of incidence must be equal to the angle of reflexion.


COLOURS and COLOURING.


COLOURS.

Chap. CCXXII.What Surface is best calculated to receive most Colours.

White is more capable of receiving all sorts of colours, than the surface of any body whatever, that is not transparent. To prove it, we shall say, that any void space is capable of receiving what another space, not void, cannot receive. In the same manner, a white surface, like a void space, being destitute of any colour, will be fittest to receive such as are conveyed to it from any other enlightened body, and will participate more of the colour than black can do; which latter, like a broken vessel, is not able to contain any thing.

Chap. CCXXIII.What Surface will shew most perfectly its true Colour.

That opake body will shew its colour more perfect and beautiful, which has near it another body of the same colour.

Chap. CCXXIV.On what Surfaces the true Colour is least apparent.

Polished and glossy surfaces shew least of their genuine colour. This is exemplified in the grass of the fields, and the leaves of trees, which, being smooth and glossy, will reflect the colour of the sun, and the air, where they strike, so that the parts which receive the light do not shew their natural colour.

Chap. CCXXV.What Surfaces shew most of their true and genuine Colour.

Those objects that are the least smooth and polished shew their natural colours best; as we see in cloth, and in the leaves of such grass or trees as are of a woolly nature; which, having no lustre, are exhibited to the eye in their true natural colour; unless that colour happen to be confused by that of another body casting on them reflexions of an opposite colour, such as the redness of the setting sun, when all the clouds are tinged with its colour.

Chap. CCXXVI.Of the Mixture of Colours.

Although the mixture of colours may be extended to an infinite variety, almost impossible to be described, I will not omit touching slightly upon it, setting down at first a certain number of simple colours to serve as a foundation, and with each of these mixing one of the others; one with one, then two with two, and three with three, proceeding in this manner to the full mixture of all the colors together: then I would begin again, mixing two of these colours with two others, and three with three, four with four, and so on to the end. To these two colours we shall put three; to these three add three more, and then six, increasing always in the same proportion.

I call those simple colours, which are not composed, and cannot be made or supplied by any mixture of other colours. Black and White are not reckoned among colours; the one is the representative of darkness, the other of light: that is, one is a simple privation of light, the other is light itself. Yet I will not omit mentioning them, because there is nothing in painting more useful and necessary; since painting is but an effect produced by lights and shadows, viz. chiaro-scuro. After Black and White come Blue and Yellow, then Green, and Tawny or Umber, and then Purple and Red. These eight colours are all that Nature produces. With these I begin my mixtures, first Black and White, Black and Yellow, Black and Red; then Yellow and Red: but I shall treat more at length of these mixtures in a separate work [52], which will be of great utility, nay very necessary. I shall place this subject between theory and practice.

Chap. CCXXVII.Of the Colours produced by the Mixture of other Colours, called secondary Colours.

The first of all simple colours is White, though philosophers will not acknowledge either White or Black to be colours; because the first is the cause, or the receiver of colours, the other totally deprived of them. But as painters cannot do without either, we shall place them among the others; and according to this order of things, White will be the first, Yellow the second, Green the third, Blue the fourth, Red the fifth, and Black the sixth. We shall set down White for the representative of light, without which no colour can be seen; Yellow for the earth; Green for water; Blue for air; Red for fire; and Black for total darkness.

If you wish to see by a short process the variety of all the mixed, or composed colours, take some coloured glasses, and, through them, look at all the country round: you will find that the colour of each object will be altered and mixed with the colour of the glass through which it is seen; observe which colour is made better, and which is hurt by the mixture. If the glass be yellow, the colour of the objects may either be improved, or greatly impaired by it. Black and White will be most altered, while Green and Yellow will be meliorated. In the same manner you may go through all the mixtures of colours, which are infinite. Select those which are new and agreeable to the sight; and following the same method you may go on with two glasses, or three, till you have found what will best answer your purpose.

Chap. CCXXVIII.Of Verdegris.

This green, which is made of copper, though it be mixed with oil, will lose its beauty, if it be not varnished immediately. It not only fades, but, if washed with a sponge and pure water only, it will detach from the ground upon which it is painted, particularly in damp weather; because verdegris is produced by the strength of salts, which easily dissolve in rainy weather, but still more if washed with a wet sponge.

Chap. CCXXIX.How to increase the Beauty of Verdegris.

If you mix with the Verdegris some Caballine Aloe, it will add to it a great degree of beauty. It would acquire still more from Saffron, if it did not fade. The quality and goodness of this Aloe will be proved by dissolving it in warm Brandy. Supposing the Verdegris has already been used, and the part finished, you may then glaze it thinly with this dissolved Aloe, and it will produce a very fine colour. This Aloe may be ground also in oil by itself, or with the Verdegris, or any other colour, at pleasure.

Chap. CCXXX.How to paint a Picture that will last almost for ever.

After you have made a drawing of your intended picture, prepare a good and thick priming with pitch and brickdust well pounded; after which give it a second coat of white lead and Naples yellow; then, having traced your drawing upon it, and painted your picture, varnish it with clear and thick old oil, and stick it to a flat glass, or crystal, with a clear varnish. Another method, which may be better, is, instead of the priming of pitch and brickdust, take a flat tile well vitrified, then apply the coat of white and Naples yellow, and all the rest as before. But before the glass is applied to it, the painting must be perfectly dried in a stove, and varnished with nut oil and amber, or else with purified nut oil alone, thickened in the sun [53].

Chap. CCXXXI.The Mode of painting on Canvass, or Linen Cloth [54].

Stretch your canvass upon a frame, then give it a coat of weak size, let it dry, and draw your outlines upon it. Paint the flesh colours first; and while it is still fresh or moist, paint also the shadows, well softened and blended together. The flesh colour may be made with white, lake, and Naples yellow. The shades with black, umber, and a little lake; you may, if you please, use black chalk. After you have softened this first coat, or dead colour, and let it dry, you may retouch over it with lake and other colours, and gum water that has been a long while made and kept liquid, because in that state it becomes better, and does not leave any gloss. Again, to make the shades darker, take the lake and gum as above, and ink [55]; and with this you may shade or glaze many colours, because it is transparent; such as azure, lake, and several others. As for the lights, you may retouch or glaze them slightly with gum water and pure lake, particularly vermilion.

Chap. CCXXXII.Of lively and beautiful Colours.

For those colours which you mean should appear beautiful, prepare a ground of pure white. This is meant only for transparent colours: as for those that have a body, and are opake, it matters not what ground they have, and a white one is of no use. This is exemplified by painted glasses; when placed between the eye and clear air, they exhibit most excellent and beautiful colours, which is not the case, when they have thick air, or some opake body behind them.

Chap. CCXXXIII.Of transparent Colours.

When a transparent colour is laid upon another of a different nature, it produces a mixed colour, different from either of the simple ones which compose it. This is observed in the smoke coming out of a chimney, which, when passing before the black soot, appears blueish, but as it ascends against the blue of the sky, it changes its appearance into a reddish brown. So the colour lake laid on blue will turn it to a violet colour; yellow upon blue turns to green; saffron upon white becomes yellow; white scumbled upon a dark ground appears blue, and is more or less beautiful, as the white and the ground are more or less pure.

Chap. CCXXXIV.In what Part a Colour will appear in its greatest Beauty.

We are to consider here in what part any colour will shew itself in its most perfect purity; whether in the strongest light or deepest shadow, in the demi-tint, or in the reflex. It would be necessary to determine first, of what colour we mean to treat, because different colours differ materially in that respect. Black is most beautiful in the shades; white in the strongest light; blue and green in the half-tint; yellow and red in the principal light; gold in the reflexes; and lake in the half-tint.

Chap. CCXXXV.How any Colour without Gloss, is more beautiful in the Lights than in the Shades.

All objects which have no gloss, shew their colours better in the light than in the shadow, because the light vivifies and gives a true knowledge of the nature of the colour, while the shadows lower, and destroy its beauty, preventing the discovery of its nature. If, on the contrary, black be more beautiful in the shadows, it is because black is not a colour.

Chap. CCXXXVI.Of the Appearance of Colours.

The lighter a colour is in its nature, the more so it will appear when removed to some distance; but with dark colours it is quite the reverse.

Chap. CCXXXVII.What Part of a Colour is to be the most beautiful.

If A be the light, and B the object receiving it in a direct line, E cannot receive that light, but only the reflexion from B, which we shall suppose to be red. In that case, the light it produces being red, it will tinge with red the object E; and if E happen to be also red before, you will see that colour increase in beauty, and appear redder than B; but if E were yellow, you will see a new colour, participating of the red and the yellow.