THE 



POPULAR SCIENCE 

 MONTHLY. 



DECEMBER, 1877. 



THE GKOWTH OF THE STEAM-ENGINE. 1 



Br Professor B. H. THUESTON, 



OF THE STEVENS INSTITUTE OF TECHNOLOGY. 

 II. 



THE STEAM-ENGINE AS A TRAIN OF MECHANISM. 



SECTION III. ' The Period of Development. Newcomen and 

 Watt, a. d. 1700 to a. d. 1800. 22. The evident defects of Sa- 

 very's engine, its extravagant consumption of fuel, the inconvenient 

 necessity of placing it near the bottom of the mine to be drained, and 

 of putting in several for successive lifts where the depth was consid- 

 erable, and, especially, the risk which its use with high pressures in- 

 volved even in its best form, considerably retarded its introduction, 

 and it came into use very slowly, notwithstanding its superiority in 

 economic efficiency over horse-power. 



23. The first important step taken toward remedying these de- 

 fects was by Thomas Newcomen and John Cawley, or Calley, two 

 mechanics of the town of Dartmouth, Devonshire, England, who pro- 

 duced what has been known as the Atmosj)heric or Newcomen En- 

 gine. 



Newcomen was a blacksmith, and Cawley a glazier and plumber. 



It has been stated that a visit to Cornwall, where they witnessed 

 the working of a Savery engine, first turned their attention. to the 

 subject ; but a friend of Savery has stated that Newcomen was as 

 early with his general plans as Savery. 



After somediscussion with Cawley, Newcomen entered into corre- 

 spondence with Dr. Hooke, proposing a steam-engine, to consist of a 



1 An abstract of " A History of the Growth of the Steam-Engine," to be published 

 by D. Appleton & Co. 



VOL. XII. 9 



