LIST OF FULL-PAGE ILLUSTRATIONS.
[CHAPTER I.]
an introduction to the study of nature.
The object of this book is to give the student who is about to enter on the study of natural science some general idea as to the conditions of the natural realm. As this field of inquiry is vast, it will be possible only to give the merest outline of its subject-matter, noting those features alone which are of surpassing interest, which are demanded for a large understanding of man's place in this world, or which pertain to his duties in life.
In entering on any field of inquiry, it is most desirable that the student should obtain some idea as to the ways in which men have been led to the knowledge which they possess concerning the world about them. Therefore it will be well briefly to sketch the steps by which natural science has come to be what it is. By so doing we shall perceive how much we owe to the students of other generations; and by noting the difficulties which they encountered, and how they avoided them, we shall more easily find our own way to knowledge.
The primitive savages, who were the ancestors of all men, however civilized they may be, were students of Nature. The remnants of these lowly people who were left in different parts of the world show us that man was not long in existence before he began to devise some explanation concerning the course of events in the outer world. Seeing the sun rise and set, the changes of the moon, the alternation of the seasons, the incessant movement of the streams and sea, and the other more or less orderly successions of events, our primitive forefathers were driven to invent some explanation of them. This, independently, and in many different times and places, they did in a simple and natural way by supposing that the world was controlled by a host of intelligent beings, each of which had some part in ordering material things. Sometimes these invisible powers were believed to be the spirits of great chieftains, who were active when on earth, and who after death continued to exercise their power in the larger realms of Nature. Again, and perhaps more commonly, these movements of Nature were supposed to be due to the action of great though invisible beasts, much like those which the savage found about him. Thus among our North American Indians the winds are explained by the supposition that the air is fanned by the wings of a great unseen bird, whose duty it is to set the atmosphere into motion. That no one has ever seen the bird doing the work, or that the task is too great for any conceivable bird, is to the simple, uncultivated man no objection to this view. It is long, indeed, before education brings men to the point where they can criticise their first explanations of Nature.
As men in their advance come to see how much nobler are their own natures than those of the lower animals, they gradually put aside the explanation of events by the actions of beasts, and account for the order of the world by the supposition that each and every important detail is controlled by some immortal creature essentially like a man, though much more powerful than those of their own kind. This stage of understanding is perhaps best shown by the mythology of the Greeks, where there was a great god over all, very powerful but not omnipotent; and beneath him, in endless successions of command, subordinate powers, each with a less range of duties and capacities than those of higher estate, until at the bottom of the system there were minor deities and demigods charged with the management of the trees, the flowers, and the springs—creatures differing little from man, except that they were immortal, and generally invisible, though they, like all the other deities, might at their will display themselves to the human beings over whom they watched, and whose path in life they guided.