The studies of the nature and form of clouds, reprinted in the following pages from the fourth and fifth volumes of Modern Painters, will be in this series third in order, as they are in those volumes, of the treatises on natural history which were there made the foundation of judgment in landscape art. But the essay on trees will require more careful annotation than I have at present time for, and I am also desirous of placing these cloud studies quickly in the hands of any one who may have been interested in my account of recent storms.

I find nothing to alter, and little to explain, in the following portions of my former work, in which such passages as the eighth and ninth paragraphs of the opening chapter—usually thought of by the public merely as word-painting, but which are in reality accurately abstracted, and finally concentrated, expressions of the general laws of natural phenomena,—are indeed among the best I have ever written, and in their way, I am not ashamed to express my conviction, unlikely to be surpassed by any other author. But it may be necessary to advise the student of these now isolated chapters not to interpret any of their expressions of awe or wonder as meaning to attribute any supernatural, or in any special sense miraculous, character to the phenomena described, other than that of their adaptation to human feeling or need.