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proportion of carbon is evidently greater than in woody 
fibre, the peat during its decay evolving its hydrogen and 
oxygen, and becoming gradually more rich in carbon. We 
will examine the nature of this change more in detail when 
we come to the consideration of the coal formations. Peat 
is extensively used as a fuel in Ireland and parts of Ger- 
many. In the latter country it is merely cut by the spade 
into the form of bricks, and dried, the surface soil and peat 
having been previously removed. In Holland, where the 
peat is an older formation, it is moulded and pressed into 
bricks by a process almost identical with the manufacture 
of bricks from clay. The objections to the use of peat 
as a fuel are its extreme lightness, porosity, and brittle- 
ness, together with the quantity of water and ash it contains. 
100 lbs. of peat contain from 1 to 33 lbs. of incombustible 
ash, derived from the vegetable matter of which it is com- 
posed. In Ireland attempts have been made to render the 
peat more portable and solid by compression in powerful 
hydraulic presses. The peat thus subjected to pressure 
loses nearly one-third of its weight of water, and from the 
increased aggregation of the particles of carbon, contains, in 
a like bulk, a much larger proportion of combustible matter. 
But the economic value of the peat is not sufficiently im- 
proved to counterbalance the expense of so costly a process ; 
as the peat is not even then sufficiently rich in carbon to 
admit of its general adoption, especially for steam purposes. 
A patent has, however, been obtained by a Mr. Hill, 
for distilling dry peat, and collecting the pyroligneous 
spirit and tar. The tar is converted into pitch, which 
he mixes while hot with peat charcoal, and thus renders a 
very bulky, and, for many purposes, valueless article, one 
of great importance. 
Peat Charcoal is prepared in two ways. First, in circular 
mounds formed by arranging from 700 to 1,000 brick- 
