To the coal mine we are also indebted for that great boon of modern civilization, the railway.
Coal is a heavy, bulky article, selling at a low price. Not only must it be removed from the earth, but it must be carried at a cheap rate, and often for long distances. Where there is no water communication the roads are the only mode of conveyance. Originally common earth roads were used, and the coal was carried in ordinary carts. These, roads were improved, and, after a time, were in the condition of stone causeways, or macadamized tracks. Afterwards wooden tracks were used, over which the wheels would roll more easily than upon ordinary roads. These wooden tracks were at first placed in the underground ways of the mines, and afterwards extended to the ways above ground.
INVENTION OF THE RAILWAY.
But wood is not durable; it soon rots and wears away. The wooden tracks were subsequently replaced by others of cast iron; originally these were grooved, but subsequently they were furnished with a lateral flange. Afterwards wrought iron was substituted for cast iron. In the first instance strips of cast iron were placed upon wooden rails, forming the old-fashioned strap rail. Afterwards was invented the ordinary rail as we now find it. The flange was removed from the rail, and placed upon the wheel, and thus, step by step, the modern railway came into existence.
Something more was wanted. Cars were propelled by means of horse or man power. It was necessary to apply the steam engine to the work of transportation. Trefethick, a Cornish miner, constructed a locomotive with a simple boiler, like that of a stationary engine; but the heating surface and the motive power were too small. It was not then supposed that the wheels would turn upon a smooth rail and move forward, and so the driving wheel was toothed and worked in a rack. The speed was less than that of a carriage drawn by horses. George Stephenson, an old coal miner, completed the locomotive.
Seguin, in France, about the same time, invented the tubes which run through the locomotive boiler, and afford a passage to the flames. They greatly increased the evaporating surface, and consequently the production of steam. Stephenson discharged into the chimney the steam which had acted upon the piston, and thus gave a great draft to the furnaces. The locomotive was then complete, and since that day it has only been improved in its details.
We have wandered a little from the search for coal to speak of the steam engine, the locomotive, and the railway.
BORING FOR COAL.
Many coal mines have been discovered by borings in search of artesian springs. About thirty years ago, in one of the French provinces, a well was being bored, and, quite unexpectedly, the boring tools revealed the presence of coal. As soon as this became known, everybody went to work searching, not for water, but for coal. In a region sixty miles long by twelve or fifteen wide, the ground was perforated like a sieve, by a series of borings which were laid down on a plan that seemed to resemble a constellation of stars on a celestial map. Everywhere coal was found, and altogether one hundred thousand acres of coal fields were added to the wealth of France. Nearly thirty companies were organized to work the new mines. Since the discovery about fifty pits have been sunk, some of them to a depth of five hundred yards. In 1851 the mines produced five thousand tons of coal. At the present day their product is not far from twenty millions of tons. All this originated in a search for water.