3^4 



ILLUSTRATIONS OF THE 



tlepofited, before they were carried to the place 

 of their ultimate deftination. 



325. But the great depth which the lake has 

 at prefent, ftill remains to be explained, becaufe 



ivel could be carried beyond the 



£> 



m u d 

 If. of 



OF gr 



fand fe 



.1 



eady to receive it. 



ep 



The 



which V 

 ty of th 



diffi 



Ity mufl be acknowledged ; and fome caufe 



tion, yet cer- 

 with which 



feems to acl. if 



in th 



tainly in t 

 ■we are b 



prefervation of lakes 



ainted. We can indeed 



imagine fome caufes of that kind to occur in 

 the courfe of the degradation of the land, which 



may produc 

 menfions of 



w 



lal 



or 



eafe th 



di 



d 



The wear 



ft 



or 



body 



6 



away of 



f Itrata, may lay b 



d 



accelTible to th 



fome beds of 



neral fubfl: 



ry 



ble in th 



t 



fluid 



The d 



ftria, for inftance, in Chefliire, which contains 

 rock- fait, extends over a tract of fourteen or fif- 

 teen miles, and is covered by a thick ftratum 

 of clay, more or lefs indurated, v/hich defends the 

 fait from the water at the furface, and preferves 



I mafs in a ftate of drynefs. Should 



the whol 



this covering be broke open by any 



vulfi 

 be ir 



or fhould it b 

 ; proc:refs of th 



ay, as it muft 



ge 



ral dqt 



th 



gain admiiTion to the faline il 



w^o 



uld 



