[ 95 ] 
proceed to the experiments made on the difiilied 
water. 
The difiilied water, efpecially that part of it which 
came over firfi, became opakefand let fall a precipitate, 
on droping into it a folution of fugar of lead. It alfo 
became opake by the addition of corrofive fublimate, 
much in the fame manner that the plain water did 
before diftillation. 
It was found, by dropping into it a little acid of 
vitriol and committing it to evaporation, to contain a 
fmall quantity of volatile alcali; as it left four grains 
of a brownifh fait, which being re-diflolved in water, 
yielded a fmell of volatile alcali on the addition of 
lime. It is doubtlefs this volatile alcali, which is the 
caufe of the precipitate, which the difiilied water 
makes with fugar of lead and corrofive fublimate. 
What firfi fuggeffed to me that the difiilied water 
contained a volatile alcali, was the diddling feme of it 
over again in a retort ; whereby the firfi: runnings 
were fo much impregnated with volatile alcali, as to 
turn paper died with the juice of blue flowers, to a 
green colour, and in fomemeafure to yield a fmell of 
volatile alcali. 
In the foregoing experiment, the fait procured 
from the difiilied water was perfectly neutral ; fo 
that the quantity of acid employed was certainly 
not more than fufficient to faturate the alcali, but 
it may very likely have been lefs ; as in that cafe 
the fuperfiuous volatile alcali would have flown off in 
the evaporation. The following experiment fhews 
pretty nearly the quantity of volatile alcali in the 
difiilied water,. 
Experi- 
