"Niccola's peculiar praise is this,--that, in practice at least, if not in theory, he first established the principle that the study of nature, corrected by the ideal of the antique, and animated by the spirit of Christianity, personal and social, can alone lead to excellence in art:--each of the three elements of human nature--Matter, Mind, and Spirit--being thus brought into union and co-operation in the service of God, in due relative harmony and subordination. I cannot over-estimate the importance of this principle; it was on this that, consciously or unconsciously, Niccola himself worked--it has been by following it that Donatello and Ghiberti, Leonardo, Raphael, and Michael Angelo have risen to glory. The Sienese school and the Florentine, minds contemplative and dramatic, are alike beholden to it for whatever success has attended their efforts. Like a treble-stranded rope, it drags after it the triumphal car of Christian Art. But if either of the strands be broken, if either of the three elements be pursued disjointedly from the other two, the result is, in each respective case, grossness, pedantry, or weakness:--the exclusive imitation of Nature produces a Caravaggio, a Rubens, a Rembrandt--that of the Antique, a Pellegrino di Tibaldo and a David; and though there be a native chastity and taste in religion, which restrains those who worship it too abstractedly from Intellect and Sense, from running into such extremes, it cannot at least supply that mechanical apparatus which will enable them to soar:--such devotees must be content to gaze up into heaven, like angels cropt of their wings."--Vol. ii., p. 102-3. * * *