Modern Painters, Volume 1 (of 5)

by John Ruskin

First: Water, of course, owing to its transparency, possesses not a perfectly reflective surface, like that of speculum metal, but a surface whose reflective power is dependent on the angle [§ 6. General laws which regulate the phenomena of water. First, the imperfection of its reflective surface.]at which the rays to be reflected fall. The smaller this angle, the greater are the number of rays reflected. Now, according to the number of rays reflected is the force of the image of objects above, and according to the number of rays transmitted is the perceptibility of objects below the water. Hence the visible transparency and reflective power of water are in inverse ratio. In looking down into it from above, we receive transmitted rays which exhibit either the bottom, or the objects floating in the water; or else if the water be deep and clear, we receive very few rays, and the water looks black. In looking along water we receive reflected rays, and therefore the image of objects above it. Hence, in shallow water on a level shore the bottom is seen at our feet, clearly; it becomes more and more obscure as it retires, even though the water do not increase in depth, and at a distance of twelve or twenty yards—more or less according to our height above the water—becomes entirely invisible, lost in the lustre of the reflected surface.

Second: The brighter the objects reflected, the larger the angle at which reflection is visible; it is always to be remembered that, strictly speaking, only light objects are reflected, and [§ 7. The inherent hue of water modifies dark reflections, and does not affect bright ones.]that the darker ones are seen only in proportion to the number of rays of light that they can send; so that a dark object comparatively loses its power to affect the surface of water, and the water in the space of a dark reflection is seen partially with the image of the object, and partially transparent. It will be found on observation that under a bank—suppose with dark trees above showing spaces of bright sky, the bright sky is reflected distinctly, and the bottom of the water is in those spaces not seen; but in the dark spaces of reflection we see the bottom of the water, and the color of that bottom and of the water itself mingles with and modifies that of the color of the trees casting the dark reflection.

This is one of the most beautiful circumstances connected with water surface, for by these means a variety of color and a grace and evanescence are introduced in the reflection otherwise impossible. Of course at great distances even the darkest objects cast distinct images, and the hue of the water cannot be seen, but in near water the occurrence of its own color modifying the dark reflections, while it leaves light ones unaffected, is of infinite value.

Take, by way of example, an extract from my own diary at Venice.

"May 17th, 4 p.m. Looking east the water is calm, and reflects the sky and vessels, with this peculiarity; the sky, which is pale blue, is in its reflection of the same kind of blue, only a little deeper; but the vessels' hulls, which are black, are reflected in pale sea green, i.e., the natural color of the water under sunlight; while the orange masts of the vessels, wet with a recent shower, are reflected without change of color, only not quite so bright as above. One ship has a white, another a red stripe," (I ought to have said horizontal along the gunwales,) 'of these the water takes no notice.'

"What is curious, a boat passes across with white and dark figures, the water reflects the dark ones in green, and misses out all the white; this is chiefly owing to the dark images being opposed to the bright reflected sky."

I have left the passage about the white and red stripe, because it will be useful to us presently; all that I wish to insist upon here is the showing of the local color (pea green) of the water in the spaces which were occupied by dark reflections, and the unaltered color of the bright ones.

Third: Clear water takes no shadow, and that for two reasons; A perfect surface of speculum metal takes no shadow, [§ 8. Water takes no shadow.](this the reader may instantly demonstrate for himself,) and a perfectly transparent body as air takes no shadow; hence water, whether transparent or reflective, takes no shadow.

But shadows, or the forms of them, appear on water frequently and sharply: it is necessary carefully to explain the causes of these, as they are one of the most eminent sources of error in water painting.

First: Water in shade is much more reflective than water in sunlight. Under sunlight the local color of the water is commonly vigorous and active, and forcibly affects, as we have seen, all the dark reflections, commonly diminishing their depth. Under shade, the reflective power is in a high degree increased,[^[61]] and it will be found most frequently that the forms of shadows are expressed on the surface of water, not by actual shade, but by more genuine reflection of objects above. This is another most important and valuable circumstance, and we owe to it some phenomena of the highest beauty.