"But where fair Isis rolls her purer wave The partial muse delighted loves to lave; On her green banks a greener wreath is wove, To crown the bards that haunt her classic grove."

Byron.

GREEN, which occupies the middle station in the natural scale of colours and in relation to light and shade, is the second of the secondary colours: it is composed of the extreme primaries, yellow and blue, and is most perfect in hue when constituted in the proportions of three of yellow to eight of blue of equal intensities; because such a green will perfectly neutralize and contrast a perfect red in the proportions of eleven to five, either of space or power, as adduced on our Scale of Chromatic Equivalents. Of all compound colours, green is the most effective, distinct, and striking, affecting the mind with surprise and delight when first produced by the mixture of blue and yellow: so dissimilar to its constituents does it appear to the untutored eye. Green, mixed with orange, converts it into the one extreme tertiary citrine; and, mixed with purple, it becomes the other extreme tertiary, olive: hence its relations and accordances are more general, and it contrasts more agreeably with all colours than any other individual colour. It has, accordingly, been adopted with perfect wisdom in nature as the general garb of the vegetal creation. It is, indeed, in every respect a central or medial colour, being the contrast, compensatory in the proportion of eleven to five of the middle primary, red, on the one hand, and of the middle tertiary, russet, on the other; and, unlike the other secondaries, all its hues, whether tending to blue or yellow, are of the same denomination.

These attributes of green, which render it so universally effective in contrasting of colours, cause it also to become the least useful in compounding them, and the most apt to defile other colours in mixture: nevertheless it forms valuable semi-neutrals of the olive class with black, for of such subdued tones are the greens, by which the more vivid hues of nature are contrasted; accordingly the various greens of foliage are always more or less semi-neutral in colour. As green is the most general colour of vegetal nature, and principal in foliage; so red, its harmonizing colour, and compounds of red, are most general and principal in flowers. Purple flowers are commonly contrasted with centres or variegations of bright yellow, as blue flowers are with like relievings of orange; and there is a prevailing hue, or character, in the green colour of the foliage of almost every plant, by which it is harmonized with the colours of its flowers; so also -

"No tree in all the grove but has its charms, Though each its hue peculiar; paler some, And of a warmish, grey; the willow such, And poplar, that with silver lines his leaf; And ash, far stretching his umbrageous arms; Of deeper green the elm; and deeper still, Lord of the woods, the long-surviving oak.

-------------- Not unnoticed pass

The sycamore, capricious in attire;

Now green, now tawny, and, ere autumn yet

Have changed the woods, in scarlet honours bright."

COWPER.

These changes of the leaf may be attributed, like those of flowers, to the various action of the oxygenous principle, in light and air, upon the carbon, or hydrogenous principle of plants, to the colouring matter of which the chemico-botanist has given the name of chromule. The general hue of green, as employed by Nature in the vegetal world, - "The green abode of life" - is a compound of blue, or grey, and citrine, according to its situation in the fundamental scale of colours: the gayer compounds of blue and yellow she reserves for the decoration of the animal creation, as in birds, shells, insects, and fossils.

The principal discord of green is blue; and when they approximate or accompany each other, they require to be resolved by the apposition of warm colours; and it is in this way that the warmth of distance and the horizon reconcile the azure of the sky with the greenness of a landscape. Its less powerful discord is yellow, which requires to be similarly resolved by a purple-red, or its principles. In its tones green is cool or warm, sedate or gay, either as it inclines to blue or to yellow; yet it is in its general effects cool, calm, temperate, and refreshing; and, having little power in reflecting light, is a retiring colour, and readily subdued by distance; for the same reasons it excites the retina less than most colours, and is cool and grateful to the eye. As a colour individually, green is eminently beautiful and agreeable, but it is more particularly so when contrasted with its compensating colour, red, as it often is in nature, and even in the green leaves and young shoots of plants and trees; and they are the most generally attractive of all colours in this respect. They are hence powerful and effective colours on the feelings and passions, and require, therefore, to be subdued or toned to prevent excitement and to preserve the balance of harmony in painting.

The general powers of green, as a colour, associate it with the ideas of vigour and freshness; and it is hence symbolical of youth, the spring of Q life being analogous to the spring of the year, in which nature is surprisingly diffuse of this colour in all its freshness, luxuriance, and variety; soliciting the eye of taste, and well claiming the attention of the landscape-painter, according to the following judicious remarks of one of the most eminent of this distinguished class of British artists: - "The autumn only is called the painter's season, from the great richness of the colours of the dead and decaying foliage, and the peculiar tone and beauty of the skies; but the spring has, perhaps, more than an equal claim to his notice and admiration, and from causes not wholly dissimilar, - the great variety of tints and colours of the living foliage, accompanied by their flowers and blossoms. The beautiful and tender hues of the young leaves and buds are rendered more lovely by being contrasted, as they now are, with the sober russet browns of the stems from which they shoot, and which still shew the drear remains of the season that is past." - Remarks on Landscapes characteristic of English Scenery, by J. Constable, Esq. R.A.