2 2 2 Dr. Pearson's Experiments and Observations 
7. Mild alkali of tartar, and likewife mild foffil alkali, 
though boiled in this liquor, did not occafion any additional 
precipitation. 
The fediment that fell, on merely Handing, from the above 
filtered liquid, was next examined. 
1. It did not diffolve in 100 times its weight of boiling hot 
concentrated acetous acid ; nor, 
2. Was it apparently acted upon by boiling with mild alkali 
of tartar; for, after decanting the clear liquid of this mixture, 
the fediment from it was not di delved by a large quantity of 
acetous acid, but readily by marine acid. 
3. This fediment immediately difappenred on pouring upon 
it a much fmaller quantity of marine acid, and alfo of acid of 
nitre, than had been applied of acetous acid, without any folu~ 
tion enfuing. 
4. To one portion of this folution in- marine acid juft 
mentioned, was added gradually lixivium of alkali of 
tartar ; after the effervefcence had ceafed to be produced, the 
firft drop occafioned a turbid appearance, and the liquid did not 
grow clear again on adding a large proportion of vinegar to 
make it four. 
5. Another portion of this folution in marine acid, 
being boiled to carry off the fuperabundant acid, was 
poured into a large proportion of lime-water, by which it was 
rendered cloudy, and did not become clear again on adding, 
concentrated acetous acid to make it four. 
6. To a third portion of this lolution in marine acid, from 
which the redundant acid had been carried off, twenty drops of 
Pruffian alkaline lixivium were added, which immediately 
turned it of a bluifh call; without diflurbing its tranfparency ; 
and, after Handing four days, a fmaller quantity of pale blue 
fediment 
