CHAPTER I.
THE OPERATION OF GEOGRAPHIC FACTORS IN HISTORY [Sidenote: Man a product of the earth's surface.] Man is a product of the earth's surface.

This means not merely that he is a child of the earth, dust of her dust; but that the earth has mothered him, fed him, set him tasks, directed his thoughts, confronted him with difficulties that have strengthened his body and sharpened his wits, given him his problems of navigation or irrigation, and at the same time whispered hints for their solution.

She has entered into his bone and tissue, into his mind and soul.

On the mountains she has given him leg muscles of iron to climb the slope; along the coast she has left these weak and flabby, but given him instead vigorous development of chest and arm to handle his paddle or oar.

In the river valley she attaches him to the fertile soil, circumscribes his ideas and ambitions by a dull round of calm, exacting duties, narrows his outlook to the cramped horizon of his farm.