The most common kinds of fuel used in the British islands, are turf or peat, and coal. Turf is found in large beds, called, in England and Scotland, peat mosses, and, in Ireland, bogs. These beds are sometimes found on the surface of the ground, and sometimes beneath layers of sand, gravel, or earth. Turf abounds in all the northern, and in some of the central countries of Europe. It not only exists in fenny plains, but, in moist tracts of mountain land, extends as far up as the trees, plants, and herbs, from which it is thought to have been first formed. In some parts of the western shores of Great Britain, it runs to an unknown distance into the sea. The depth of bogs or mosses varies from a few feet to twelve or fifteen yards. Sometimes it exists in a half fluid state, studded with tufts of rushes; but when more solid, heath and coarse grass grow upon it, and in the dry season afford pasture for sheep, and even for cows and horses. In deep bogs, the upper part of the peat does not burn so well as that at the bottom. In most places, it is cut with sharp spades into solid masses of the size and form of bricks. It dries slowly by being laid out in the open air, and when hard is used for firing. It kindles very fast, burns with a bright flame, and forms a pleasant fire; but it consumes quickly, and does not throw out so much heat as coal. Coal abounds more in England than in any other part of the world. It is sometimes found near the surface of the earth, but is more often dug from deep pits or mines. It runs along the earth in veins or beds; one of which, in the north of England, has been traced eight hundred feet below the surface of the ground, and so far under the sea, that ships of the largest burden can float over the men's heads, while they are at work. To prevent the earth from falling in, huge massive pillars of coal are left standing here and there. Long ago, the foul air, which collects under ground, used some E times to be set on fire by the lamps of the miners, and, blowing up with a loud, report, to kill many of them on the spot; but this does not occur so often now, since Sir Humphrey Davy found out a kind of gauze, which keeps in the flame, and prevents it from kindling the foul air. A lamp with a piece of this gauze round about it, is called a safety lamp. 1 |