The earliest movement on water, we may suppose, was equally crude and simple. Some observant savage noticed that wood did not sink, and later found out by experiment that a floating log would remain on the surface even when his own weight was added. The rude dug-out followed the discovery. The stick or limb by which the dug-out was pushed and turned shaped itself at length into the lighter and more effective paddle; the hollowed log was succeeded by a framed and covered structure, the paddles became oars; and thus was evolved in prehistoric times the type of all later boats on lake and stream. It was centuries after this—no one knows how many—before the force of wind was utilized by the invention of sails, and when that immense advance was achieved the enduring era of ship-building commenced. Roughly speaking, then, we may assign to the first stage in the development of transport such results as were obtained by the muscular strength of man, whether applied directly to the articles carried or used in propelling the clumsy vehicles and water craft which he had constructed. The motive power in all cases was the unaided energy of his own body. And no later addition to the resources then at his command, it should be observed, has wholly displaced the original method. The natural powers of locomotion have not only remained unabated, but have greatly increased by experience and training. Indeed, the manual handling of articles of property must always be an important incident of ownership and exchange, since no mechanical device can meet all the needs of transfer or equal the delicacy and dexterity of our bodily organs. Nor should we overlook in this connection the many-sided ingenuity which has been displayed in constructing and perfecting a great variety of vehicles for hand propulsion. The latest examples of this ingenuity are the light racing shells which can be rowed with such remarkable rapidity, and that unique and fascinating machine, the up-to-date bicycle. These are at once the survival and the consummation of primitive transportation, that is to say, transportation where human energy is the motive power. To the second stage of this development belongs the great increase of force which was obtained by the subjugation of animals and their employment for land transportation, and by the use of sails and rudders which multiplied many times the efficiency of water carriage. When these two results were secured, man had added to his own bodily powers the superior strength of beasts of burden and the enormous energy derived from the winds of heaven. This was an immeasurable gain and marked the beginning of that wonderful civilization which slowly followed. The animal kingdom was brought into service for the varied functions of land distribution, and the ship which could be sailed and guided made every waterway subservient to man’s requirements.