256 ESSAYS anp OBSERVATIONS 
| fit long by the fire, grow faintifh: It alfe 
turns the bottom of their veflels white; 
Peats taken from moffes, free of all mine- 
rals, have none of the above mentioned, 
or any other bad effect. 
As to the matter itfelf, that differs in 
many refpects; fo that in the fame mofs, 
_ according to thé different depth of it, there 
are three or four kinds of peats found. 
In North Britain, in the province of Gro- 
ningen, and in feveral other places, that | 
which is uppermoft, is light and {pungy; 
further down, better; and at bottom is. 
a fubftance that is black, and makes a 
firm folid peat. - 
In Holland, that which lies uppermoft 
is beft, being of a dark or black colour, 
to which others fucceed of different colours 
and fubftances not fo good. That which 
is light and {fpungy, taken from a barren 
heathy ground, or from a dry fandy foil ; 
alfo fuch mofs as is much mixed with pie- 
ces of rotten wood, roots, mud, gravel, 
or fand, or which, confuming quickly, 
leaves behind a great many impurities 
mixed with its afhes, is bad. 
PEATS 
