Such Pebbles as are found here in Strata near the 
Surface of the Earth, are much more brittle, and 
break eafier without Comparifon, than thofe which 
lie in deeper Strata: For, if the firft of thefe fall, 
but with their own Weight, upon any other Stone, 
from the Height of 5 or 4 Feet, they will break very 
frequently into ten or a dozen Pieces * whereas fuch 
as are found deep in the Earth will endure being 
thrown againft one another with all the Force one 
can give, and that too twenty times perhaps, before 
the lead Splinter of them can be broken off. 
I have conftantly found, that the more clean 
and tranfparent the Sands are with which our 
Pebbles are mix'd, the more beautiful the Pebbles 
themfdves are, however different their Colours 
be. 
It is wonderful to obferve and confidcr with what 
amazing Skill the Creator of all Things hathdifpofed 
the different Strata of the Earth, to ferve the Pur- 
pofes of His Wifdom. 
The vegetable Mould or Surface of the Earth is 
compounded or made up of Sands, Clays, Marls, 
Loams, rotten Stalks, and Leaves of Herbs, 
ferving as a proper Bed and Covering, as well as a 
Receptacle and Conductor of Moifture, to the Roots 
of Trees and Plants in general. 
Sands and Pebbles may be confider'd as Drains for 
carrying off the redundant Moifture, to where it may 
be ready to fupply the Place of what is continually 
rifing in Exhalations ; but, left the Strata of Sand 
fhould be too thick, fmall ones of Clay are often 
placed between, and feem intended to prevent this 
Moifture from departing too far from where 
