[Sidenote:  Origin of navigation.]

Man’s normal contact with the sea is registered in his nautical achievements.  The invention of the first primitive means of navigation, suggested by a floating log or bloated body of a dead animal, must have been an early achievement, of a great many peoples who lived near the water, or who in the course of their wanderings found their progress obstructed by rivers; it belongs to a large class of similar discoveries which answer urgent and constantly recurring needs.  It was, in all probability, often made and as often lost again, until a growing habit of venturing beyond shore or river bank in search of better fishing, or of using the easy open waterways through the thick tangle of a primeval forest to reach fresh hunting grounds, established it as a permanent acquisition.

[Sidenote:  Primitive forms.]

The first devices were simply floats or rafts, made of light wood, reeds, or the hollow stems of plants woven together and often buoyed up by the inflated skins of animals.  Floats of this character still survive among various peoples, especially in poorly timbered lands.  The skin rafts which for ages have been the chief means of downstream traffic on the rivers of Mesopotamia, consist of a square frame-work of interwoven reeds and branches, supported by the inflated skins of sheep and goats;[528] they are guided by oars and poles down or across the current.  These were the primitive means by which Layard transported his winged bull from the ruins of Nineveh down to the Persian Gulf, and they were the same which he found on the bas-reliefs of the ancient capital, showing the methods of navigation three thousand years ago.[529] Similar skin rafts serve as ferry boats on the Sutlej, Shajok and other head streams of the Indus.[530] They reappear in Africa as the only form of ferry used by the Moors on the River Morbeya in Morocco; on the Nile, where the inflated skins are supplanted by earthen pots;[531] and on the Yo River of semi-arid Sudan, where the platform is made of reeds and is buoyed up by calabashes fastened beneath.[532]

[Sidenote:  Primitive craft in arid lands.]

In treeless lands, reeds growing on the margins of streams and lakes are utilized for the construction of boats.  The Buduma islanders of Lake Chad use clumsy skiffs eighteen feet long, made of hollow reeds tied into bundles and then lashed together in a way to form a slight cavity on top.[533] In the earliest period of Egyptian history this type of boat with slight variations was used in the papyrus marshes of the Nile,[534] and it reappears as the ambatch boat which Schweinfurth observed on the upper White Nile.[535] It is in use far away among the Sayads or Fowlers, who inhabit the reed-grown rim of the Sistan Lake in arid Persia.[536] As the Peruvian balsa, it has been the regular means of water travel on Lake Titicaca since the time of the Incas, and in more primitive form it appears among the Shoshone Indians of the