Page:Devonshire Characters and Strange Events.djvu/605

Rh engine. The system of the Marquess of Worcester was propulsion of cold water by the introduction of a blast of steam. Papin suggested the use of a vacuum formed by condensation of steam, so as to work a piston; and this vacuum in a cylinder he formed first by exploding gunpowder in it; and, as this did not answer, by removing the fire every time the condensation was required—a clumsy and impracticable method. Savery formed the vacuum first by dashing cold water against the cylinder, then by forming an outer ring of cold water about the receiver; but this did not answer well, as this body of water rapidly heated. Moreover, he did not adopt the piston, but drew up the water from mines by suction. Then came Newcomen, who adapted the piston in a cylinder to Savery's engine; and finally Newcomen and Savery together discovered how to chill and condense the steam by an injection of cold water. Papin undoubtedly suggested the leading lines on which the steam engine was to be constructed, but he was unable effectually to apply his ideas or to rectify defects in such machines as he suggested. The solution was due to Newcomen and Savery.