In glancing over these photographic sketches, one cannot avoid being struck by the silent but impressive eulogium which nature pronounces, through their agency, on the works of the more eminent masters. There is much in seeing nature truthfully, and in registering what are in reality her prominent markings. Artists of a lower order are continually falling into mere mannerisms--peculiarities of style that belong not to nature, but to themselves, just because, contented with acquirement, they cease seeing nature. In order to avoid these mannerisms, there is an eye of fresh observation required--that ability of continuous attention to surrounding phenomena which only superior men possess; and doubtless to this eye of fresh observation, this ability of continuous attention, the masters owed much of their truth and their power. How very truthfully and perseveringly some of them saw, is well illustrated by these photographic drawings. Here, for instance, is a portrait exactly after the manner of Raeburn. There is the same broad freedom of touch; no nice miniature stipplings, as if laid in by the point of a needle--no sharp-edged strokes: all is solid, massy, broad; more distinct at a distance than when viewed near at hand. The arrangement of the lights and shadows seems rather the result of a happy haste, in which half the effect was produced by design, half by accident, than of great labour and care; and yet how exquisitely true the general aspect! Every stroke tells, and serves, as in the portraits of Raeburn, to do more than relieve the features: it serves also to indicate the prevailing mood and predominant power to the mind. And here is another portrait, quiet, deeply-toned, gentlemanly,--a transcript apparently of one of the more characteristic portraits of Sir Thomas Lawrence. Perhaps, however, of all our British artists, the artist whose published works most nearly resemble a set of these drawings is Sir Joshua Reynolds. We have a folio volume of engravings from his pictures before us; and when, placing side by side with the prints the sketches in brown, we remark the striking similarity of style that prevails between them, we feel more strongly than at perhaps any former period, that the friend of Johnson and of Burke must have been a consummate master of his art. The engraver, however, cannot have done full justice to the originals. There is a want of depth and prominence which the near neighbourhood of the photographic drawings renders very apparent: the shades in the subordinate parts of the picture are more careless and much less true; nor have the lights the same vivid and sunshiny effect. There is one particular kind of resemblance between the two which strikes as remarkable, because of a kind which could scarce be anticipated. In the volume of prints there are three several likenesses of the artist himself, all very admirable as pieces of art, and all, no doubt, sufficiently like, but yet all dissimilar in some points from each