All About Engines

The Pioneers before Watt 27 Gustaf de Laval, applied this method of using the force in a jet of steam in the turbine which bears his name. But these inventions were still far short of an engine of practical value. A number of clever men de- voted the greater part of their lives to the problem before it was even partially solved. Denis Papin, a French Huguenot, spent many years at it. He studied medicine at the University of Paris, and afterwards assisted the still more famous French- man Huygens in some of his experiments. Forced, with many other Protestants, to flee from France in 1681, he lived for some years in London, where he was Curator of the Royal Society. Then he migrated to Germany and became Professor at the Univer- sity of Marburg. Early in his career he constructed an improved pump for raising water out of mines, made a diving bell, and showed how water could be raised to a temperature higher than its ordinary boiling point by heating it in a vessel in which the lid was held down by a weight. On this last account he may be regarded as the inventor of the safety valve. In 1674 Papin tried to raise water by the explo- sion of gunpowder. A tall cylinder was fitted with a piston. The bottom of the cylinder was capable of being removed. A charge of gunpowder and a slow match were placed on this, which was immedi- ately fixed in position. When the explosion occurred the piston was driven to the top of the cylinder, and as it fell by its own weight it pulled down a