In this textbook, by a few observations pupils are led to group all objects into the three Kingdoms of Nature--"Animal," "Vegetable," and "Mineral." Again, by observing differences, the Animal Kingdom is readily divided into five Sub-Kingdoms--"Vertebrates," "Annulates," "Mollusks," "Radiates," and "Protozoans." Each sub-kingdom is still further divided into Classes. Thus the sub-kingdom Vertebrates consists of five classes--"Mammals," "Birds," "Reptiles," "Amphibians," and "Fishes." The term "class" in this sense becomes a technical zoological term; so, again, the division of a "class" into several "orders." By easy steps the learner is led to group together the rodents, ruminants, and the carnivorous animals, etc.; yet the technical terms, class and order, have been avoided. There has been no attempt whatever to still further subdivide into "genera" and "species." In the Natural History, so far as possible, American species have been substituted for foreign ones; and in the chapter on Rock Formations, that portion which treats of the continental development of North America has been substituted for the author's geological history of France. In short, such corrections and changes have been made as would materially enhance the value of the book in the hands of beginners in science in America. The complete work of M. Paul Bert consists of seven parts: I. Animals; II. Plants; III. Minerals and Rock Formations; IV. Physics; V. Chemistry; VI. Animal Physiology; and VII. Vegetable Physiology. [This content was translated by Marc F. Vallette and revised and enlarged by John Mickleborough.]