Peat and Its Uses

The value of peat for fuel varies greatly, like its other qualities. Only those kinds which can be cut out in the shape of coherent blocks, or which admit of being artificially formed into firm masses, are of use in ordinary stoves and furnaces. The powdery or friable surface peat, which has been disintegrated by frost and exposure, is ordinarily useless as fuel, unless it be rendered coherent by some mode of preparation. Unripe peat which contains much undecomposed moss or grass roots, which is therefore very light and porous, is in general too bulky to make an effective heating material before subjection to mechanical treatment.

The best peat for burning, is that which is most free from visible fiber or undecomposed vegetable matters, which has therefore a homogeneous brown or black aspect, and which is likewise free from admixture of earthy substances in the form of sand or clay. Such peat is unctuous when moist, shrinks greatly on drying, and forms hard and heavy masses when dry. It is usually found at a considerable depth, where it has been subjected to pressure, and then has such consistence as to admit of cutting out in blocks; or it may exist as a black mud or paste at the bottom of bogs and sluices.

The value of peat as fuel stands in direct ratio to its content of carbon. We have seen that this ranges from 51 to 63 per cent. of the organic matter, and the increase of carbon is related to its ripeness and density. The poorest, youngest peat, has the same proportion of carbon as exists in wood. It does not, however, follow that its heating power is the same. The various kinds of wood have essentially the same proportion of carbon, but their heating power is very different.