Dr. North on Fuel. 75 
where it is wanted than any other, and probably the most 
easily obtained. There may be exceptions, however, to so 
very general a ~ 
Addenda. 
The reading of Dr. McCulloch’s valuable essay, since thé 
p ing was written, has made these addenda necessary. 
Dr. McCulloch adopts the cotmmon opinioh, that peat is de- 
composed or dead vegetable matter, and that the whole of 
such matter always originates from vegetables growing on its © 
surface. He has given full botanical catalogues of the ee 
which he supposes contribute to the ee of the di 
ent kinds of peat. 
‘For the sake of a text to make re me, upon, the follow- 
ing passages are selected from different parts of ae en Ge! 
He says, “‘ As the increase of peat kee vith t 
one is implied in that of the other, with the ex ception * trans- 
ported peat, which does not directly depend upon the same 
éause. That it may be renovated after cutting, it is necessa- 
ry that the process of vegetation be renewed, where it has. 
been thus suspended.” It is evident, from fer f the 
essay, that the Doctor means the process of v vegetation among 
the various plants only, which shoot their roots into the peaty 
matter. 
Again: “ The time required for the production of a given 
depth of peat, has been a frequent subject of inquiry. In 
some cases its growth has been so rapi to be sensible to 
cessary to have Seng to evidence, founded on circum- 
stances i longer p of time than human 
noes ‘Again? UTORSE Beet” on the continent of 
Vities of seven feet in aes, made by 
peat for — have been filled up with it, in the short space of 
avourable circumstances are however said 
to be ietetary for such a result. The present writer, from 
a comparative mode of judging, thinks such a cavity in our 
climate, under favourable circumstances, would fill up in less - 
time than thirty years. But then he doubts whether the peat 
would sooner become sufficiently solid, bie and woody, 
to be profitable for fuel. The peaty matter itself grows, as 
well as the plants whose roots are found init. Water is need- 
