C 107 ] 



being impregnated with certain Stony 

 Particles, by Degrees petrifies, and grows 

 to the Hardnefs of a Spar, and confifts 

 of feveral Coats. Under this Head are 

 comprehended all the various Kinds of 

 Incruftations, petrified Ificles, Peas-ftones, 

 and other Kinds of Spars, that do not 

 fhoot from the Subflance of the Rock, 

 but infenfibly encreafe in Bulk, preferv- 

 ing always a fmooth and curious Surface. 

 They are, for the moft part, found in 

 fubterranean Caverns, in Grottos on the 

 Appenine and Pyrenean Mountains, in Der- 

 by/hire^ and many other fuch like Places ; 

 Ibme of them refemble Sugar Plumbs, 

 and are called Confetti di ^ivoli. Thefe 

 laft are of the Kind of Spars called 6"/^- 

 lagmodiaugia. The Stala^ites take ma- 

 ny different Nam.es, according to the 

 Colour and Degree of Purity they pof- 

 fefs. They are daily formed, which many 

 found under the Arches of fVeJlminJier 

 Bridge, and in a Vault under the Terras 

 at M^indfcr^ fufficiently teftify. 



F6 We 



