converge, the eye, being forced to the centre, becomes stationary; in like manner, if all diverge, it is forced to fly off in tangents: as if the great laws of Attraction and Repulsion were here also essential, and illustrated in miniature. If we add to these Breadth, I believe we shall have enumerated all the leading phenomena of Harmony, which experience has enabled us to establish as rules. By _breadth_ is meant such a massing of the quantities, whether by color, light, or shadow, as shall enable the eye to pass without obstruction, and by easy transitions, from one to another, so that it shall appear to take in the whole at a glance. This may be likened to both the exordium and peroration of a discourse, including as well the last as the first general idea. It is, in other words, a simple, connected, and concise exposition and summary of what the artist intends. We have thus endeavoured to arrange and to give a logical permanency to the several principles of Composition. It is not to be supposed, however, that in these we have every principle that might be named; but they are all, as we conceive, that are of universal application. Of other minor, or rather personal ones, since they pertain to the individual, the number can only be limited by the variety of the human intellect, to which these may be considered as so many simple elementary guides; not to create genius, but to enable it to understand itself, and by a distinct knowledge of its own operations to correct its mistakes,--in a word, to establish the landmarks between the flats of commonplace and the barrens of extravagance. And, though the personal or individual principles referred to may not with propriety be cited as examples in a general treatise like the present, they are not only not to be overlooked, but are to be regarded by the student as legitimate objects of study. To the truism, that we can only judge of other minds by a knowledge of our own, we may add its converse as especially true. In that mysterious tract of the intellect, which we call the Imagination, there would seem to lie hid thousands of unknown forms, of which we are often for years unconscious, until they start up awakened by the footsteps of a stranger. Hence it is that the greatest geniuses, as presenting a wider field for excitement, are generally found to be the widest likers; not so much from affinity, or because they possess the precise kinds of excellence which they admire, but often from the _differences_ which these very excellences in others, as the exciting cause, awaken in themselves. Such men may be said to be endowed with a double vision, an inward and an outward; the inward seeing not unfrequently the reverse of what is seen by the outward. It was this which caused Annibal Caracci to remark, on seeing for the first time a picture by Caravaggio, that he thought a style totally opposite might be made very captivating; and the hint, it is said,