1 of by curious Men, may be drawn to
countenance their erroneous Opinion, who
would fain perſwade us, That Glaſs is
penetrable by Air properly ſo called.Our
Experiment was briefly this: We were
diſtilling a certain ſubſtance, that much a-
bounded with ſubtle Spirits and volatile
Salt, in a ſtrong Earthen-veſſel of an un-
uſual ſhape, to which was luted a large
Receiver, made of the courſer ſort of
Glaſs, (which the Trades-men are wont
to call Green-glaſs) but in our abſence,
the Fire, though it were to be very ſtrong,
was by the negligence or miſtake of thoſe
we appointed to attend it, ſo exceſſively
increaſ'd, that when we came back to the
Fornace we found the Spirituous and Sa-
line Corpuſcles pour'd out (if I may ſo
call it) ſo hot, and ſo copiouſly into the
Receiver, that they made it all opacous,
and more likely to flie in pieces, then fit
to be touch'd.Yet, being curious to ob-
ſerve the effects of a Diſtillation, prſe-
cuted with ſo intenſe and unuſual degree
of heat, we ventur'd to come near, and
obſerv'd among other things, that on the
out-ſide of the Receiver, at a great di-
ſtance from the juncture, there was ſetled
a round whitiſh Spot or two, which at
countenance their erroneous Opinion, who
would fain perſwade us, That Glaſs is
penetrable by Air properly ſo called.Our
Experiment was briefly this: We were
diſtilling a certain ſubſtance, that much a-
bounded with ſubtle Spirits and volatile
Salt, in a ſtrong Earthen-veſſel of an un-
uſual ſhape, to which was luted a large
Receiver, made of the courſer ſort of
Glaſs, (which the Trades-men are wont
to call Green-glaſs) but in our abſence,
the Fire, though it were to be very ſtrong,
was by the negligence or miſtake of thoſe
we appointed to attend it, ſo exceſſively
increaſ'd, that when we came back to the
Fornace we found the Spirituous and Sa-
line Corpuſcles pour'd out (if I may ſo
call it) ſo hot, and ſo copiouſly into the
Receiver, that they made it all opacous,
and more likely to flie in pieces, then fit
to be touch'd.Yet, being curious to ob-
ſerve the effects of a Diſtillation, prſe-
cuted with ſo intenſe and unuſual degree
of heat, we ventur'd to come near, and
obſerv'd among other things, that on the
out-ſide of the Receiver, at a great di-
ſtance from the juncture, there was ſetled
a round whitiſh Spot or two, which at