THE REVOLUTIONS OF THE CRUST OF THE EARTH. 355 



the human race, as to the history of its infancy, it is lost in the night of 

 the past, and we can only accept the assertion of M, de Quatre-fages,* 

 proved by the contradictory results of the researches of the many dis- 

 tinguished savana 'engaged with these questions, that science has not 

 even commenced to solve this important problem. 



It has been attempted to estimate at least the antiquity of man of 

 the age of the deposits which contain human implements. The Tinierei 

 a stream which empties into the lakeof Geneva, hasat its mouth a cone 

 formed by the torrent which, having been cut transversely by the rail- 

 road, was observed by M. Morlott to consist of strata corresponding to 

 the three ages of man. From the thickness of these strata, and from 

 other local circumstances which must have influenced the formation of 

 the cone, we arrive at an age of 10,000 years for the three strata. This 

 estimation is not exaggerated, since these strata represent only a part of 

 the deposit formed during each age ; for a large portion must have been 

 carried away by contemporary erosion. 



The skull found in the alluvion of Mississippi implies, it is claimed, 

 an age of 50,000 years. An analogous age of man is indicated by the 

 peat-bogs of Denmark. The lover strata of these bogs contain the 

 remains of the Scotch pine, the middle show a predominance of the oak, 

 which in the upper is replaced by the beech. Man preceded the oak ; he 

 inhabited this country when the Scotch pine formed vast forests, as is 

 proved by the traces of cutting instruments found in the trunks of the 

 pine trees preserved in the bogs, as well as by the flint instrument 

 found in the same stratum with this conifer.^ 



"We ought to say that all these estimates are relative, as well to 

 the mode of sedimentation of the alluvion as to the formation of the 

 peat-bogs, which may modify them considerably; still we may with 

 safety conclude that man is much more ancient than we have been 

 accustomed to believe. 



Without entering into the question of the unity or diversity of the 

 origin of the human race, let us consider what influence man has exer- 

 cised upon the organic and inorganic worlds. When the first genera- 

 tions appeared, man, few in numbers, confined his activity to the 

 search for food, for means of shelter, and defense against the attack 

 of animals. In proportion as the number of men increased, and fruit, 

 game, and other alimentary resources began to fail, man was impelled 

 to greater exertion, in order to supply his needs and to protect himself 

 from the variable influence of external condition. He learned to store 

 his provisions, and to capture animals, which in time became tame, and 

 so were laid the foundations of agriculture and domestication, the two 

 powerful elements of progress and well-being of the human race. Since 

 then man has made such progress that he now uses, to bring him into 



*Origine des species animales et ve'getales, Revne des Deux Mondes, t. lxxx, 1869, [>■ 672. 

 t Bull. Soc. Geolog., 1860, second series, t. xviii, p. 829. 

 t Fr. Troyon, L' Homme fossile, p. 17f>. 



