THUS ends a book, composed in solitude, and almost without the cognizance of a single human being, for the sole purpose (or as nearly so as may be) of improving the knowledge of mankind, and through that medium their happiness. For reasons which need not be specified, the author’s name is retained in its original obscurity, and, in all probability, will never be generally known. I do not expect that any word of praise which the work may elicit shall ever be responded to by me; or that any word of censure shall ever be parried or deprecated. It goes forth to take its chance of instant oblivion, or of a long and active course of usefulness in the world. Neither contingency can be of any importance to me, beyond the regret or the satisfaction which may be imparted by my sense of a lost or a realized benefit to my fellow-creatures. The book, as far as I am aware, is the first attempt to connect the natural sciences into a history of creation. The idea is a bold one, and there are many circumstances of time and place to render its boldness more than usually conspicuous. But I believe my doctrines to be in the main true; I believe all truth to be valuable, and its dissemination a blessing. At the same time, I hold myself duly sensible of the common liability to error, but am certain that no error in this line has the least chance of being allowed to injure the public mind. Therefore I publish. My views, if correct, will most assuredly stand, and may sooner or later prove beneficial; if otherwise, they will as surely pass out of notice without doing any harm.