NATURAL HISTORY. 19 



and shells, are removed to great distance?. Trans- 

 portations of this kind must therefore go on in every 

 part of the ocean ; and the matters transported, after 

 having subsided, must raise eminences similar to the 

 composition and structure of our mountains. We 

 must not however imagine that these matters cannot* 

 be carried to a great distance ; for we daily find grain, 

 and other productions of the East and West Indies, 

 landing on our coasts. These bodies may be said to 

 be specifically lighter than the water, and the other 

 substances specifically heavier. Yet as they arc re- 

 duced to an impalpable powder, they may be long 

 suspended in the water, and consequently transported 

 to any distance. 



It has been imagined that the agitation, produced 

 by the winds and tides, docs not affect the bottom, 

 when it is very deep. But the truth is, tliat whate- 

 ver be the depth, the power which occasions the flux 

 and reflux operates equally upon every particle of the - 

 mass at the same time. It therefore appears that the 

 tides, the winds, and whatever else gives birth to mo- 

 tion in the sea, must produce heights and inequalities 

 in its boUoiir; and that these eminences must uni- 

 formly be composed of regular strata, either horizon- 

 tal or inclined. 



Whenever civinencc.s are formed they interrupt the 

 uniform motion of the waters, and produce new ones 

 called currents. Between two neighbouring heights 

 in the bottom of the ocean, there must be a current 

 which will follow their common direction, and, like a 

 river, cut a channel, the angles of v.hu h will be alter- 

 nately opposite through the whole of its course. 

 These heights must continually increase, ss ti 

 tor will depoit its ordinary ?edicr:ent upon their ri 



