[ i8 3 ] 
and the blue can be poured off ftill dlffufed in the 
water, from which however it foon feparates, and fails 
to the bottom. It is not poflible entirely to free the 
blue from the peaty matter, for, after above twenty 
different additions of water, there were flail ftreaks 
of black interfperfed through it, when it was allowed 
to fubfide ; neither have I ever been able to feparate 
all the blue from any of the black part. 
When a little water is added to a quantity of it, it 
acquires fome degree of tenacity, and when a fmall 
portion of water is allowed to ftand on its furface for 
a day or two, the water becomes of a yellowifh co- 
lour. 
Thefe are the chief circumftances relating to its 
natural hiftory, and the obvious properties it difcovers 
without the afliftance of chemical operations. The 
following are the experiments I have made upon it, 
with a view to difcover its nature more particularly. 
In order to find whether there was any part of it 
ibluble in water, I palled a large quantity of water, 
which I hadufed in feparatingthe black from it, through 
a filter, and then fet it to evaporate in B M ; but there 
was nothing; left in the veffel after the evaporation, 
except fome earth, which the water had probably 
contained in itfelf. 
To a quantity of the blue powder, I added the 
common vitriolic acid of the (hops j a degree of ef- 
fervefcence enfued, and a conliderable froth remained 
for fome time on the furface j the whole was changed 
into a dark brown colour, and, when filtrated, the 
folution was a tranfparent brown liquor. A conlide- 
rable fediment remained behind on the filter ; but I 
am inclined to think, that this confided chiefly of the 
peaty 
