38 MAMMALIA. 



vessels become gradually obstructed, the solids become rigid, and, after a life 

 more or less long, more or less agitated, more or less painful, old age arrives 

 with decrepitude, decay, and death. Man rarely lives beyond a hundred years, 

 and most of the species, either from disease, accident, or infirmity, perish long 

 before that term. 



The child requires the assistance of its mother long after it has ceased to 

 derive its nourishment from her; from her it obtains an education both moral 

 and physical, and a mutual attachment is created that is fervent and durable. 

 The nearly equal number of the two sexes, and the difficulty of sup- 

 porting more than one wife, prove that monogamy is the mode of union 

 most natural to our species. From the long period of infantile weakness 

 springs domestic subordination, and the order of society in general, as the 

 young people who compose the new families continue to preserve with their 

 parents those tender relations to which they have so long been accustomed. 

 This disposition to mutual assistance multiplies to an almost unlimited extent 

 those advantages previously derived by insulated man from his intelligence ; 

 it has assisted liim to tame or repulse other animals, to defend himself from 

 the effects of climate, and thus enabled him to cover the earth with his species, 



In other respects, he appears to possess nothing resembling instinct, no 

 regular habit of industry produced by innate ideas ; his knowledge is the 

 result of his sensations and of his observations, or of those of his predecessors. 

 These transmitted by speech, increased by meditation, and applied to his neces- 

 sities and his enjoyments, have originated all the arts of life. Language and 

 letters, by preserving acquired knowledge, are a source of indefinite perfection 

 to his species. It is thus he has acquired ideas, and made all nature contribute 

 to his wants. 



There are very different degrees of development, however, in man. 



The first hordes, compelled to live by fishing and hunting, or on wild fruits, 

 and being obliged to devote all their time to search for the means of subsistence, 

 and not being able to multiply greatly, because that would have destroyed the 

 game, advanced but slowly. Their arts were limited to the construction of 

 huts and canoes, to covering themselves with skins, and the fabrication of 

 arrows and nets. They observed such stars only as directed them in their 

 journeys, and. some few natural objects whose properties were of use to them. 

 They domesticated the dog, simply because he had a natural inclination for 

 their own kind of life. When they had succeeded in taming the herbivorous 

 animals, they found in the possession of numerous flocks a never-failing source 

 of subsistence, and also of some leisure, which they employed in extending the 

 sphere of their acquirements. Some industry was then employed in the 

 construction of dwellings and the making of clothes : the idea of property was 

 admitted, and consequently that of barter, as well as wealth and the difference 

 of conditions, those fruitful sources of the noblest emulation and of the vilest 

 passions : but the necessity of searching for fresh pastures, and of obeying the 

 changes of the seasons, still doomed them to a wandering life, and limited 

 their improvements to a very narrow sphere. 



