( 1P7 ) 
Ton by rarifying the Blood, and enflaming tbe Stomach to 
fuch a. degree, that the Vefiels can no more recover their 
tone, which he found to be exaftly the cafe in a Dog, upon 
which he made the Experiment, For the Cure he recon> 
mends Acid Medicines and Lixivial Salts. Generous Wines 
(the Antients Remedy) help only by diffoiving the clammy 
Refinous parts. 
Tiie laft Eflay is of Venomous Stems and Damps^ in Latm 
icalled Mephites^ixom a Syriac Theme fignifying to breath. Of 
this fort the Mephitis of HierapDlk, and the Specm Coriciu^ 
were famous of old. They are frequent in Couiitries thai 
abound with Minerals or Subterraneous Fires. The moft 
celebrated of all, is the GrMa de C<^nt near Naples in Italp 
which the Dr hath vifited-5;-and given an accurdte defcri-ption 
of it. The Fumes which here arife but to a determinate 
height and then turn downwards, and fall back to the 
Earth, being drawn into the Lungs, both expeli the Air 
out of the VeJicuU and pofiefling its room, ftreighten the 
paflage of the Blood Veflels. How this comes to be fo de- 
ftru&ive will appear to them/ who fhall attentively read- 
the Theory of Refpiration here inferred, and founded 
upon Mechanical Principles. He proceeds from hence to 
treat of Peftilential Fevers, what conftirution or tempera- 
ment of Air inclines to them, how the SymptoiBs appear 
in rheir firft Rife, Prog^-efs and Height, concluding with 
fome cautions about Waters^ whicii as thc7 are fomerimes 
faturated with Metalline, Lapideous orSiline Particles, 
produce ill , confequences in the Bodies of Men, different 
according to the hrtngrh ot the Tinctures, or the parti-- 
cular . nature of the pjrncieSj, or the part of the Body where- 
in they are depofiicd. 
, That the Reade r m''y have a ji:ft Idea of this perfor- 
mance, I think vfi^iry to adcl ro what harh -ecu (aid- 
in the extrad. i h:u tne cu^lc- .nt and Poiiie feearn- 
ing, with whicii k iS well ilore.i is the fmalleit.part ot 
T tttttt its 
