MAN FROM THE FARTHEST PAST 
camels, in the Old World, and llamas, distant cousins of the 
camel, in the New. Then some inventive genius, perhaps 
inspired by his own tendency to drag things he could not 
pick up, found that an animal could haul a great deal more 
behind him than he could carry on his back. This great 
discovery led step by step to the utilization of animals for 
drawing plows and carts. 
Out of this idea grew that of the wheeled cart, the origin 
of which, however, fades out in prehistoric darkness. Prob- 
ably some sort of sledge came first, some contrivance like 
the travois of the North American Indians—two poles 
lashed to the animal’s sides, with the load placed on the 
part that trailed along the ground. From something of 
this sort must have developed a sledge on the order of the 
“stone boat’’ used by farmers for hauling loads of stones. 
The inventive powers of Neolithic man in most portions 
of the world seem to have been unequal to producing the 
wheel in even its simplest form. The most advanced 
peoples of the New World, like the Incas, the Mayas, and 
the Aztecs, remained wholly ignorant of it before the white 
man came. Even the ancient Egyptians appear to have 
acquired it late—long after they knew the plow; and 
it did not reach southern Africa, northern Asia, and the 
Pacific area till late historic times. 
In all probability the wheel was invented only once, 
most likely in southeastern Asia, and from that region it 
has gradually spread over the whole earth as we see it to- 
day. We may surmise that it developed out of the log 
roller which we still see placed under heavy burdens to 
ease them over the ground. To save himself the trouble 
of having to pick up rollers after the load had passed over 
them and then run around and place them on the ground 
in front of it again, some prehistoric inventor hit on the 
scheme of driving pegs into the under surface of his sledge 
to keep the roller dragging along between them as it 
turned. Next, to lessen the friction against the ground, 
the middle section of the log was cut away all around, 
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