“A GENERALIA.--The divisions of this main class comprise most of the rules, methods and factors which are of general application, and which qualify or pervade every branch of science, industry or human study. They are universal and pervasive, and cannot be logically assigned to any other single main class as peculiar or germane to it. “B, C, D PHYSICAL SCIENCES.--Matter, force, motion and their applications are assumed to precede life and mind, and for that reason the material side of science, with its applications, has been selected as a foundation main class on which to construct the system. “E, F BIOLOGICAL SCIENCE.--Life and its forms, arising out of matter, occupy the second place among the main classes, and here are put general biological theories and facts, followed by plant and animal life, each in an ascending order from low to high forms of organization. “G, H ETHNOLOGICAL AND MEDICAL SCIENCE.--Human life, its varieties, physical history, disorders and recreations, follows naturally as a higher development of plant and animal life, and completes the biological chain. “I ECONOMIC BIOLOGY AND DOMESTIC ARTS.--The applications of plant and animal life to human needs, placed midway between the physical and mental attributes of man as indicating the primitive exercise of mind, and to assemble in one sequence the chief biological subjects. As a matter of practical convenience, rather than logical necessity, it was thought better to keep composite subjects like Agriculture, Clothing, Foods, etc.--involving questions of origin, use and manufacture--all in one place, close to the main classes from which they are derived, rather than to distribute them more closely at Botany or Zoology. “J, K PHILOSOPHY AND RELIGION.--Mental attributes, order and beliefs of human life, following naturally from its physical basis, and primitive manifestation in the instinct of procuring food and clothing. “L SOCIAL AND POLITICAL SCIENCE.--Social order and laws of human life. Placed here because, although society or family and other tribal organizations may have preceded religion, mind as embodied in philosophy must have preceded both. “M LANGUAGE AND LITERATURE.--Communication and recording in human life. The spoken, written and printed word, which grew as a necessity out of the primitive operations of mind. “N LITERARY FORMS.--The products of communication and recording in human life in their more imaginative forms; placed here on the ground that fable probably preceded more formal history. “O-X HISTORY, GEOGRAPHY, BIOGRAPHY.--The actions, records and descriptions of human life and its dwelling-place. Arranged in this order and at this place because of their intimate connexion. Geography, although logically related to Physiography and Biography to Ethnology, are, nevertheless, as a matter of practical utility, and because of the literature actually existing, more naturally grouped here than separated.