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a confiderable Thicknefs, yet without lofing their 
Form. They were found in the Tyber at Rome. 
JEtites, Eagles Stones. Pliny the Naturalift fays, 
that Eagles cannot hatch their young without hav¬ 
ing one of thefe Stones in their Neft ; but, it is 
to be looked upon as a mere idle Eifbon, the Ex¬ 
perience of many fucceeding Ages being far from 
warranting the Afiertion. 
Under this Title are ciaffed all the hollow Pebbles; 
thofe which particularly bear this Name have another 
enclofed in theCavity of them, which may be known 
by their Rattling. In others is very plainly heard a 
Liquid, which on opening them is only found to 
be foul Water; this Kind is called Enhydres. When 
they have an earthy Matter inclining to the Cryftal- 
line in them, they take the Name of Geodes ; and 
when there are in one Stone two or three Cavities, 
they have of late been fometimes called Lithozomi. 
Thefe Stones have had many other Names •, as, 
Eutccium , Echites , Erodialis , Aquileius , and Lapis 
pregnans. Great Virtue has been by Women afcri- 
bcd to the Eagle-fione, it being thought by many, 
that, if it is worn above the Girdle, it prevents 
Abortion; if about the Knee, it helps Delivery : 
But this Virtue is ideal, and only a Conjecture 
formed from its being pregnant, as it were, of ano¬ 
ther Stone. Credulity and Superftition often pro¬ 
duce Fancies, which one i-s furprifed to find People 
of Senle and Reafon fometimes give way to ; but 
fuch is the Frailty of human Nature. 
Helmintholithi. In this Oafs Linnaus ranks all 
the fofTil Shells. The Stones under this Tide are 
fuppofed to have been originally a Kind of Coral, 
which, by being buried in the Earth for fome con- 
Bderable Space of Time, has at length arrived to a 
jState of Petrifaftion > but the Name imports Earth 
D 4 Worm 
