afcribes to the friendly effluvia from tiie earth, andar^ 
giaes from the obfervations in Hungary, and Bohemia^ , 
where the Air is impregnated with mineral exhalationSa . 
fuitablc to the Oar the Earth contains under it. He af- 
firms it alfo probable that in divers places iome Endemi- 
caldileafes do at leaft in part depend upon fubterraneal 
Steamsefpecially where the caufe of the diftemper can- 
not otherwife be accounted for, if together with this we 
confider the pervioufnefsof human bodys,& the penetrat- 
ing quality of mineral expirations, of which he gives ma- 
ny experimentsXaftly, he difcourfes of peftilential Fea- 
vers, and of the Plague it felf, as to whofe being natural 
or fupernaturaljhe affents rather to its being the former s 
his entire judgment about which confifts of two parts,one, 
that it is exceeding difficult C0 affign the true and adse- 
quate caufe of the origineofthepeftilence; and the o- 
ther that what ever be the caufe of its firft eruption, 'its . 
propagation, and divers of its Symptomes may be proba- 
bly enough referred to the depravation of the Air by 
fubterranealSteams, and their effecSls, &c. He defcribes 
the Emplaftrum attradivum Peflilentiale , together 
with the Magnes Arfenicalis a chief ingredient of it ; and 
difcovers his opinion and experience of the great efficacy 
of Goats- rue in Malignant diftempers, but when Medi- 
cine fails, thofe difeafes generally appearing under new 
fliapes, he accounts for the iudden ceafing of the conta- 
gion, among other ways, by the afceniion of fumfes of 
a. contrary nature, which though perhaps in themfelves 
iinwhoiefome, may never theleis cornbine with the pef- 
tileatial ones, into a third kind^ altogether innocent. 
