[ &73 ] 
with which the whole Neck of the Glafs Veflel was 
filled, to fublide confiderably. When the redifh 
fulphureous Air in the upper Part of the Glafs is clear, 
by Handing two or three Hours, if then the Mouth 
of the inverted Glafs is lifted our of the Water, fo 
as to let the Water in the Neck of the Glafs fall out ; 
which, luppofing it to be a Pint, then an equal Quan- 
tity of frdh Air will rufh in at the Mouth of the 
Neck of the Veflel, which mud immediately be im- 
merfed in the Water : And upon the Mixture of 
the frefh Air with the then clear fulphureous Air, 
there will inftantly arife a violent Agitation between 
the two Airs, and they will become, from tranfpa- 
rent and clear, a redifh turbid Fume, of the Colour 
of thofe Vapours which were feen feveral Evenings 
before the late Earthquakes : During which EfFcrvcf- 
cence, a Quantity of Air, nearly equal to what 
frdh Air was let in, will be deftroyed ; which is 
evident by the riling up of the Water in the Neck of 
the Glals, almoft as high as before. And if, after 
the Eftervefcencc of the mixed Airs is over, and be- 
come clear again, frefh Air be admitted, as before, 
they will again grow reddifh and turbid, and deftroy 
the new admitted Air as before ; and this after fe- 
veral repeated Admiffions of frefh Air : But after 
every Readmiflion of frefh Air the Quantity deftroyed 
will be lefs and lefs, till no more will be deftroyed. 
And it is the fame after Handing feveral Weeks, pro- 
vided, in the mean time, too much frefh Air had 
not been admitted. Now, I found the Sum total 
of the frefh Air thus deftroyed to be nearly equal to 
the firft Quantity of fulphureous Air in the inverted 
Glafs. 
R r r r 
Since 
