CHAPTER XVI 



MAN'S WAY OF HELPING HIMSELF 



149. Labor-saving Devices. To primitive man belonged 

 more especially the arduous tasks of the out-of-door life : the 



clearing of paths through 

 the wilderness ; the haul- 

 ing of material ; the break- 

 ing up of the hard soil of 

 barren fields into soft loam 

 ready to receive the seed ; 

 the harvesting of the ripe 

 grain, etc. 



The more intelligent 



FIG. 91. - Prying a stone out of the ground. r aces among men SOOn 



learned to help them- 

 selves in these tasks. For example, our ancestors in the field 

 soon learned to pry stones out of the ground (Fig. 91) 

 rather than to undertake the almost impossible task of lifting 

 them out of the earth in which they were embedded ; to swing 

 fallen trees away from a path by means of rope attached to 

 one end rather than to attempt to remove them single-handed ; 

 to pitch hay rather than to lift it ; to clear a field with a rake 

 rather than with the hands ; to carry heavy loads in wheelbar- 

 rows (Fig. 92) rather than on the shoulders; to roll barrels 

 up a plank (Fig. 93) and to raise weights by ropes. In every 

 case, whether in the lifting of stones, or the felling of trees, 

 or the transportation of heavy weights, or the digging of 

 the ground, man used his brain in the invention of mechanical 



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