PRELIMINARY REPORT ON PEAT.

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 io% 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 c f 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, and 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 purroses. It is said to be clean and easily kindled, to burn steadily, with considerable heat, and little or no smoke, sparks, soot or cinders, 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 advantageous 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 problem 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

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