$ Reafons for Juppofing that 
of the water without vache their roots to the 
bottom. 
The matter of Peat- is silat of vegetable 
Origiit, as well as the treacherous covering men- 
tioned above. ‘The ufe to which it is commonly 
applied, fhews that it is fit for combuftion ; and its 
afhes contain a quantity of fixed Alkali; which is 
rarely, however, pure, or free from mineral falts. 
If we examine its ftructure, it will be difcovered to 
confift principally of flexible, branched fibres, va- 
rioufly interwoven, and twifted together. Their 
arrangement proves, that they grew where they 
are lodged; and that they were not brought into 
their prefent fituation by any extraordinary agent, 
fuch as an inundation; for, had this been the cafe, 
inftead of a compact fubftance, we fhould have 
found an incoherent mafs of heterogeneous things, 
thrown loofely together without texture or connection. 
The lighteft and moft porous parts, being firft fa- 
turated with humidity, would have defcended to the 
bottom; whilftthe more compact fubftances, being 
leaft capable of receiving an addition to their weight 
by imbibing water, would have remained in the 
higheft place. ‘Thus we fhould have found the 
materials of a f{wamp difpofed in /ftrata according to 
their texture and fpecific gravity, provided they had 
all been depofited at the fame time in their prefent 
fituation; which fuppofition cannot be true, becaufe 
it is contradictory to Fact. The light, friable earth 
‘intermixed with thefe fibres has originated from the 
decompofition 
