ENTRANCE TO A COAL MINE.
DOWN IN A COAL MINE.
INVENTING THE STEAM ENGINE.
In the eighteenth century deep pits in the Newcastle coal fields were filled with water, and it was necessary to drain these pits before the coal could be taken out. The ordinary pump was not sufficient for the purpose, and a more powerful engine became necessary. Inventions seem to come at a time when they are most needed. When the necessity for a powerful pump was greatest, the steam engine was invented. Savery, Newcomen, and Watt succeeded each other. Captain Savery constructed one of his “fire engines” to lift water from one of the Cornish mines; but the power of the engine was not great, and the quantity of water raised was exceedingly small.
Newcomen invented the atmospheric steam engine, in which the piston was lifted by steam, and when this was condensed the piston was forced to the bottom of the cylinder by the pressure of the atmosphere. Afterwards Watt improved upon the engine, and overcame the difficulty of removing the vast accumulations of water in the deep mines, about the middle of the eighteenth century.
There is a curious relation between coal mines and the steam engine. The latter was invented among the former, and without its application to pumping purposes the invention would have been to a great extent worthless, for by means of the very substance raised from the mines the engine is kept in motion. The mines thus furnished the material with which the engine is operated, and only with the aid of the engine can the coal mines be properly worked.
In the petroleum regions of America the borings and pumpings are frequently conducted by means of the gas which rises from the earth. Very often a steam engine is run without any other fuel than a stream of natural gas, conveyed beneath the boiler, and fed through a proper distributing apparatus.