The great defect in nearly all the photographic pictures which are obtained is the extreme contrast between the high lights and the shadows, and in many an entire absence of the middle tones of the picture.

In the very beautiful productions of Mr. Buckle, of Peterborough, which were displayed in the Great Exhibition, there was a very remarkable degree of fine definition, united with a beautiful blending of the respective parts which constituted the picture. There was no glaring contrast between the lights. Those parts which were the most brilliantly illuminated were softened into the middle tones of the picture, and those again faded gradually into the deep shadows. In the works of M. Martin and M. Flàcheron, whose processes I have given, the same harmonizing of lights and shadows was generally found to exist.

The usual mistake with amateurs is that of selecting bright sunshine as the period for operating. It is thought, when a cathedral, for example, is brilliantly lighted up by sunshine, is the time for obtaining a photographic copy of it. A little reflection will convince the operator that this is the case only under particular conditions.

When the projecting parts of the building are flooded with sunshine, they cast the deepest possible shadows; consequently, in the photographic picture the prominent points would appear brilliantly white, and the shadows intensely dark.

It will be understood that I refer always to the positive, or completed picture.

A clear blue sky, reflecting its light upon a similar structure, produces less prominent illumination of the bold ornamental parts, and gives more light to those parts on which the shadows are cast. A photograph taken under such conditions of light and shade will be far more beautiful than the spotted productions which ordinarily result from the practice of operating when the sun is shining brightly on the object.

In the same manner, when the sun shines brightly on the leaves of trees, a very large quantity of light is reflected from their surfaces, the other parts appearing by contrast in almost absolute shadow. Hence, nearly all photographic views of forest scenery have more the appearance of scenes which have been sprinkled with snow than foliage glowing with sunshine.

An artist studies in his productions the most effective disposition of the lights and shadows, and it is by the harmonious disposition of these that he succeeds in giving a peculiar charm to his productions. Nearly all photographic pictures, although they have the merit of strict truthfulness, appear to want this great beauty of art. This has mainly arisen from the circumstance that intense illumination has been sought for under the idea of producing the sharpest picture; and it is true that thus we do obtain a very perfect definition of outline. Many productions are remarkable for this, and, indeed, reproduce with unnatural exactness all the minute details of the objects copied; whereas the human eye never sees this extraordinary sharpness of outline in nature; upon the edges of every object there are fringes of light which soften off their outlines, and subdue the general tone of objects, blending all harmoniously. Perhaps there is more than ordinary difficulty in producing this in a representation of nature which is effected by means of a lens. The artist may, however, do much : all times, even of bright illumination, are not fitted for producing a picturesque photograph. Nature should therefore be looked at with an artist's eye, and the happy moment chosen when the arrangements of light and shade give the most picturesque effects, and when these are in a condition to be correctly reproduced according to the laws by which actinic influences are regulated.