of the Pyrites. z6i 



and fecondarily to copper ; as by deftru&ion thefe 

 two metals ar^ufually very eafily reducible to fuch 

 earths; not but that^iey may degenerate (tho 5 not 

 become of another fpeciesj from the unkindlinefs of 

 the foil and other rircumftances. And thefe damps 

 are to be confidered as different as the feveralj^n/** 

 themfelves are, and as univerfal as the pyrites it- 

 klf is. 



As to the fecond thing, namely, whence thefe 

 damps, or the feeds of pyrites arife ; we have three 

 things to confider here. 



(i.) Dry bodies, as earth and ftone; only the 

 parts of the former lay fpongy and loofe on each 

 other, but thofe of the latter baked firm ; and, at 

 times, feem as if run or melted together: whence 

 ftone may be produced from earth, and earth again 

 from ftone. Now the queftion is, whether thefe 

 laft exhale. 



We have three forts of ftone ; namely, marl- 

 ftone, lime-ftone, and flint-ftone. Marl -ftone, 

 which has ceafed to be an earth, and commenced a 

 ftone, not only crumbles in the air, but proves 

 a good manure for vegetables; various inftan- 

 ces of which I have mentioned in my Flora Sa- 

 turnizans-, particularly, one from Oberauin Mifnia, 

 which fufficiently fhews the affinity between the ve- 

 getable and mineral kingdoms. But for this ftone 

 to contribute any thing to the growth of plants, it 

 muft be refolved, whereby the refolving moifture 

 of the air does not fo much crumble its earth, as 

 rather extract fomething from it ; not take it up as 

 a fine powder, but fwallow it up in fuch a manner, 

 that the earth, by means of the water, is no longer 

 an earth, and as little a water, but a third kind of 



S 3 glutinous 



