474 INDUSTRIAL INSTITUTIONS. 



conspire to establish a distinction between the ruling mili 

 tant class and the subject industrial class. 



This primary differentiation is followed by secondary 

 differentiations when growth permits. Speaking of the insti 

 tution in Greece, Heeren, after noting that slaves did 

 domestic work and agricultural work, as well as labour in 

 mines and galleys, goes on to say: 



&quot;Most, if not all, trades were carried on by slaves, who were uni 

 versally employed in the manufacturing establishments. In these not 

 only the labourers, but also the overseers were slaves ; for the owners 

 did not even trouble themselves with the care of superintending, but 

 farmed the whole to persons who were perhaps often the overseers also, 

 and from whom they received a certain rent, according to the number 

 of slaves, which they were obliged to keep undiminished.&quot; 



Still more marked was the sub-differentiation in the still 

 more militant society of Rome. For as w r e have already 

 seen, not only were those who carried on manual occupations 

 and those who superintended them, members of the slave- 

 class, and not only did this class include those who carried 

 on commerce, but it included also those who carried on the 

 higher mental activities the professional class. Out of 

 these slave-classes were formed all social structures save 

 those occupied with war and government. There should be 

 added the significant fact that the organization of these ser 

 vile bodies simulated in some measure the militant organiza 

 tion; since the slaves on a Roman estate were arranged into 

 groups of ten called decurice, under a decurion, mostly also a 

 slave but sometimes a free man : they were regimented. 



In later times throughout Europe, while war was chronic, 

 there arose an analogous though not identical differentiation 

 analogous in so far that the sustaining part of each society 

 was definitely marked off from the expending part. 



799. Between that worst form of slavery in which there 

 is legally recognized no distinction between the bondman 

 and the brute, and the most mitigated form of slavery occur, 



