PRELIMINARY REPORT ON PEAT. 
307 
for a few weeks, or until it is dry enough to burn. This is the way 
in which it is used chiefly by the peasants of Europe, in districts 
where other fuel is scarce and labor is cheap. But air-dried peat 
is rather bulky and friable, and while it is burning a good deal of 
its fuel value is wasted in evaporating the 10% or more of water 
which it always contains even after being dried for an indefinite 
period. If, however, the Florida peat is less retentive of water 
than that from most other parts of the world, as the analyses seem 
to indicate, the last-named objection would not have so much force 
here. 
In order to produce peat fuel economically on a large scale it 
must be compressed by machinery before drying, or after partial 
drying. This diminishes all three of the objections just mentioned. 
The amount of water can be still further reduced by the application 
of heat before, during, or after compression, but obviously there 
is a limit to the amount of heat which can be profitably applied to 
a substance which is itself to be used only as a source of heat. To 
expel all the water would require nearly as much heat as the 
finished product would produce by its combustion, for peat retains 
the last drops of water with great tenacity. 
Numerous types of machinery have been devised for preparing 
peat fuel for the market, and they have been described in some of 
the reports previously mentioned, particularly that of Davis on 
Michigan peat.. In most of them, or at least in the best known 
ones, the peat as it comes from the bog is first macerated so as to 
break up the vegetable tissues and thus facilitate the escape of the 
water, and then squeezed between rollers and pressed into moulds, 
somewhat as clay is treated in the process of brick-making. The 
blocks are then dried in a shed or other suitable place, a^d in a few 
days or weeks they are ready for use. 
Those who have used pressed peat as fuel are almost unanimous 
in testifying that it is very satisfactory, especially for domestic pur¬ 
poses. It is said to be clean and easily kindled, to burn steadily, 
with considerable heat, and little or no smoke, sparks, soot or cin¬ 
ders, and to be well adapted to both grates and stoves. In short, 
its fuel properties are just about intermediate between those of 
wood and coal. 
For industrial uses it has in some places been found advanta¬ 
geous to subject peat to a process of destructive distillation in iron 
retorts, separating it into gas and coke, just as is done every day 
with coal. This has the special advantage of simplifying the pro¬ 
blem of transportation, for peat at its best is too bulky to be carried, 
far with profit, while the gas can be piped for miles and burned 
