REVOLUTIONS. 9<J 



When it is considered, that the business of the ehace has 

 ever been keenly followed by man, from the first stages of 

 society to the psgsent day ; that its triumphs have been 

 eagerly sought after, and highly prized ; and when these 

 circumstances are united, with the recollection of the num- 

 bers of the human race dispersed over the globe, all prose- 

 cuting the same purpose, for the long period of nearly 6000 

 years, it does not appear unreasonable to conclude, that 

 man has effected many changes in the geographical distri- 

 bution of animals. Perhaps, he may have succeeded, in the 

 course of this long period of persecution, in completing the 

 destruction of several species, the memorial of which tradi- 

 tion has failed to preserve, while their remains may yet be 

 traced in the newer and perhaps older alluvial deposits. 



However great those changes may have been, in the con- 

 dition of certain species, brought about by human agency, 

 there are many other revolutions which have taken place 

 in the animal kingdom, over which man could exercise no 

 control. Many corals and shells, the bones of fish, rep- 

 tiles and quadrupeds, are imbedded in stone, which have 

 belonged to species which do not now exist in a living state 

 on the globe, and which, probably, were extinct before 

 man exercised any control. By what cause, then, have 

 these revolutions been effected ? 



When we attend to the physical conditions of tempera- 

 ture, food, situation, and foes, which must at all times have 

 exercised their influence over the existence and geographi- 

 cal distribution of animals, it will appear obvious, that a 

 variety of causes, (a change in one or all of these condi- 

 tions,) may have operated in promoting the increase of 

 some species, and in producing the decay or extinction of 

 others. Have we, then, any proof of such changes in the 

 truths of geognosy, or in the alterations which we witness 

 taking place on the surface of the globe ? 



