( * 9 © ) 
wou’d in the common way of breathing ; This he 
propofes as ufeful to thofe who have occafion to go into 
Places where the Air is infed:ious ; but where the 
noxious Vapours are not very denfe, Mufflers only of 
Cloth or Flannel impregrated with Salt of Tartar 
may ferve, as he found by feveral Experiments, 
He Ihews afterwards the Reafons why Tulvis 
fulminans has more Force than Gun-Powder, and con- 
firms Sir Ifaac Newton*s account of Fire and Flame 
(fiuery 9, and 10, of his Opticks() but Ihews X^t.Nieu- 
iventyisy Dt.Boerhaave's and Mon^L* Emery's Account of 
Fire to be erroneous; but that it was not the matter 
of Fire, but Elaftick Air which that laft nam’d Gen- 
tleman had fo often obferv’d to be loft in the Analyfis 
«f Bodies. 
That the artifical Sulphur made by Monf Geofroy^ 
was inflammable chiefly on account of the Air fup- 
plied to it by the Oil of Tartar. 
That if Fire was a peculiar Matter in Sulphur, it 
ought to dilate, not to condenfe, the Air ; as it appears 
to do by Experiment. That Fire confifts in the AdFion 
and Rcadion between repellent Air and attraeftin^g 
Sulphur ; and that Heat is communicated by the 
iEthereal Medium mention’d by Sir Jfaac Mewton in the 
laft Edition of his Opticks, 
That Fermentation will difiblve Bodies v/ithout the 
Help of included Fire, ading according to its feveral 
Degrees; a lower Degree of it ffuch as attends every 
inteftine Motion) not being inconliftent with the 
healthy State of Plants and Animals. 
That acid Particles by their great attradfive Force 
difiblve Bodies, rufliing towards their Particles, fo as 
to excite Heat, ,,and lhake afunder fome of them, 
^and turn them into Air. 
That 
