Whatever interest may be possessed by a collection of detached papers, issued at considerable intervals during a term of several years, and written without special reference one to the other, or, at the first, with any view to subsequent publication, depends as much upon the date at which they were composed, and the condition of affairs then existent, as it does upon essential unity of treatment. If such unity perchance be found in these, it will not be due to antecedent purpose, but to the fact that they embody the thought of an individual mind, consecutive in the line of its main conceptions, but adjusting itself continually to changing conditions, which the progress of events entails.