The effects of semi-transparent mediums in some natural productions seem alluded to in the following passage—"Nature sometimes accidentally imitates figures in stones and other substances, and although they are necessarily incomplete in form, yet the principle of effect (depth) resembles the Venetian practice." In a passage that follows there appears to be an allusion to the production of the atmospheric colours by semi-transparent mediums.192
NOTE Y.—Par. 672.
The author's conclusion here is unsatisfactory, for the colour of the black races may be considered at least quite as negative as that of Europeans. It would be safer to say that the white skin is more beautiful than the black, because it is more capable of indications of life, and indications of emotion. A degree of light which would fail to exhibit the finer varieties of form on a dark surface, would be sufficient to display them on a light one; and the delicate mantlings of colour, whether the result of action or emotion, are more perceptible for the same reason.
NOTE Z.—Par. 690.
The author appears to