It is unquestionably true that coal, in those regions where it is abundant, is the best and most available source of fuel, it is equally true that in many localities peat offers advantages which are not to be overlooked. The universality of its distribution and the ease with which it can be obtained, render a general knowledge of its character and capabilities very important.
It is said that one tenth of Ireland is covered by bogs, and one of the deposits of peat along the banks of the Shannon is fifty miles long and two or three broad. The origin of peat is pretty well understood. It is in all cases the remains of decayed vegetables, either trees or lower forms of growth. . It would seem that, in general, we owe our most extensive deposits of peat to one of the lower forms of vegetation, known as sphagnum or moss, the material so frequently used by nurserymen for packing plants.
This plant has the curious property of growing on the surface of a bog while its own roots are decaying at a short depth below. In this way, layer after layer is formed and deposited-the carbon being taken almost entirely from the atmosphere, so that the limits of the increase of the bog are practically limited only by the local features of the land in which the bog is formed. From the mode of their formation, it results that bogs are found to contain peat in two forms, fibrous and pasty. In the latter, the process of decomposition has proceeded farther than in the other, in which are found vegetables which still retain their fibrous character. In addition to this grand difference, it is found that peat from different bogs, and even from different parts of the same bog, varies greatly in the percentage of mineral matter which it contains.
In some kinds of peat, the amount of muck is very small, while in others it amounts to seventy per cent of the mass. Such peat is, of course, worthless. Therefore, in estimating the general value of peat, or of any given process for bringing it into use, regard must be had to the special character of the particular specimen on hand. No process and no machine can make a good article of fuel out of a poor specimen of peat, or even out of the surface peat from a generally good bog. While, therefore, in a locality where other fuel is scarce and where a good article of peat is found, it will pay well to use it as fuel, it will certainly never pay to attempt to work up such a peat as is found in many of the small bogs which are scattered over the country. The methods and machines which have been devised for the purpose of utilizing peat are almost innumerable. The oldest plan is to cut the peat, or turf, as it is sometimes called, into brick-shaped masses, which are dried by the sun and wind, and stored away under cover, either of regular roof or simple thatch. Such peat burns well and gives out a good deal of heat; but it will not answer for very intense fires, as a strong draught disintegrates it with too much rapidity. The same is true of that form of peat which is made by working the disintegrated peat into a paste with water, forming it into bricks and drying it in the sun.
In order that peat may stand the strong blast of engines and other fires, it must be rendered compact, and it has been attempted to accomplish this by means of a machine which applied to it a powerful pressure. Owing, however, to the fibrous character of the peat, it is exceedingly elastic, and the pressure is no sooner removed from its surface than it expands and becomes porous. To remedy this it was found necessary to remove or destroy the fibrous character of the material. This was most easily accomplished by means of a cutting or grinding apparatus, which made the peat into a very fine pulp totally devoid of all fibres, perfectly inelastic, and assuming by simple drying a density or cohesiveness which enables it to resist the disintegrating effects of even a blast-furnace. We have recently seen some peat which had been manufactured by the Central Peat, Fuel, and Machine Company, of Connecticut, at their works, three miles north of Meriden, and it had almost the hardness and density of hard coal. Yet this peat had been prepared without any artificial pressure, the peat pulp having been deposited in moulds and allowed to dry of its own accord. We are confident that such a process applied to any really good raw material will turn out an article of fuel which can not be surpassed, and, with the improved machines manufactured and sold by the company to which we have referred, the dry, merchantable peat can be prepared at a very moderate cost- say $1.50 to $2 per ton. At this price, it will prove in many localities to be the cheapest available source of heat.