I have been led perhaps into too great detail in illustrating these points; but I think it is of no small importance to prove how in all cases the imagination is based upon, and appeals to, a deep heart feeling; and how faithful and earnest it is in contemplation of the subject matter, never losing sight of it, or disguising it, but depriving it of extraneous and material accidents, and regarding it in its disembodied essence. I have not, however, sufficiently noted in opposition to it, that diseased action of the fancy which depends more on nervous temperament than intellectual power; and which, as in dreaming, fever, insanity, and other morbid conditions of mind is frequently a source of daring and inventive conception; and so the visionary appearances resulting from various disturbances of the frame by passion, and from the rapid tendency of the mind to invest with shape and intelligence the active influences about it, as in the various demons, spirits, and fairies of all imaginative nations; which, however, I consider are no more to be ranked as right creations of fancy or imagination than things actually seen and heard; for the action of the nerves is I suppose the same, whether externally caused, or from within, although very grand imagination may be shown by the intellectual anticipation and realization of such impressions; as in that glorious vignette of Turner's to the voyage of Columbus. "Slowly along the evening sky they went." Note especially therein, how admirably true to the natural form, and yet how suggestive of the battlement he has rendered the level flake of evening cloud. Sec. 8. The action of contemplative imagination is not to be expressed by art. I believe that it is unnecessary for me to enter into farther detail of illustration respecting these points; for fuller explanation of the operations of the contemplative faculty on things verbally expressible, the reader may be referred to Wordsworth's preface to his poems; it only remains for us, here, to examine how far this imaginative or abstract conception is to be conveyed by the material art of the sculptor or the painter. Now, it is evident that the bold action of either the fancy or the imagination, dependent on a bodiless and spiritual image of the object, is not to be by lines or colors represented. We cannot, in the painting of Satan fallen, suggest any image of pines or crags,--neither can we assimilate the brier and the banner, nor give human sympathy to the motion of the film, nor voice to the swinging of the pines. Sec. 9. Except under narrow limits.--1st. Abstract rendering of form without color. Yet certain powers there are, within due limits, of marking the thing represented with an ideal character; and it was to these powers that I alluded in defining the meaning of the term ideal, in the thirteenth chapter of the preceding section. For it is by this operation that the productions of high art are separated from those of the realist.