II : \ - 1 TION FROM TRIBAL SOCIETY 293 



muilation of wealth. As long as m-n lived from hand 

 'iioutli an<l consumed imnic.l ;i |l that was pro- 



duced, no enduring basis for formidahlo pow. <L 



i to store their food supply in ftV 



and herds an.: <*nd upon cultivated plants for their 



sul .it was pc to lay aside an 



fun. I of supplies, a Mirplus which could be drawn upon 



in time of famine or nth. With th- /ation 



'iarchal BO< no an established 



itution. ami -la\ cry becalm an important -..rial sys- 



. Th. of war was rmployrd as a cowherd or 



a sln'phrnl. Sinre large flocks can IK? att nl .1 hy rela- 

 ti\r|\ fr\\ -..-n, slavery did not reach its most 



rm of development until opportunity was af- 

 led for the use of lar.ir* numbers. The pressure of 

 population upon tin* food supply developed a system of 

 riiltix atin- tin- -oil which, though arduous, was profitable, 

 vi.led a good supply of labor could be hinl. The slave 

 i into agricultural labor and cultivation of the 

 soil wa i 1 on upon a large scale. I'.y tin- em- 



ployment of gangs of slaves it was possible to produce 



^e the surplus. I.ut if there 

 t unity i i nir- the surplus products of 



locali; ! arti-- i th-r n-irions. tl. 



was a definite limil surplus prodi; 



It was only with the growth of barter ami the increas- 



-sihilit> hanging surplus products that it be- 



ue profitable to augment both one's land and one's 



r agricultural production must 

 p anl trade open up before slavt be 



hiirhly lu. in a-Mition to the existence of a 



market, one other condition was essential to the spread of 



ttgelignuui. op. of., PP . 1M 162. 



