257 



The change of wood into stone is not the only won- 

 der here. The sand is also changed into -vagle stones. 

 These stones are found two or tiiree lingers breadth 

 beneath the surface of the earth, in little mines, some 

 paces long and broad, about half a mile from each 

 other. It is thoug.it that in these places, there oozes 

 out of the earth a sort of metallic matter, which 

 ferments with the burning sand, and in fermenting 

 assumes some kind of roundish figure, and attaches to 

 itself more and coarser sand. Afterward it hardens 

 by degrees, and grows black througa the heat of the 

 sun. 



The Eagle-stone when in the mine is soft and brit- 

 tle as an egg, and of a bright yellow or violet colour, 

 but after being expos d to the air it turns brown or 

 black, and hardens gradually. Likewise after a few 

 days most of these atones vuil if struck, suuud like- 

 little bells, 



Not far off is a vast heap of sand, which they 

 call the eagle stone hill, because it is covered over 

 -with great rocks of the very same matter whereof 

 the small eagle stones are formed. 



But what shall we judge of those petrified shells, 

 which have been dug up in many places? Some in. 

 ik-ed are not petrified. Near Reading, in Berkshire, 

 for succeeding generations, a continued body of oys- 

 tt % r-shells have been found through the circumference 

 of five or six acres of ground. Beneath is a hard, 

 rocky chalk, on which the shells lie in a bed of green 

 sand, about two feet thick. Above are various strata 

 for at Jeast'eighteen feet. The shells are so brittle, 

 that in digging, one of the valves \viil frequently drop 

 from its fellow. But several are dug out entire;, 

 nay, some double oysters, with all liieir valves united. 



In a quarry, at the cast end of Broughton, in Lin- 

 colnshire, there is a clay under the stone, i\\ allied 

 are numberless fragments of th.o .shells of shell -foil of 



