SECT, i.] THE STEAM ENGINE. 5 



These numbers are' obviously proportional to the capacity of the cylinders. 



The table is continued in the original to show the effect of a number of cylinders 

 of the largest of the above sizes, each one being capable of raising 3240 Ibs. 



Morland has given the increase of volume, which water occupies in the state of 

 vapour at common pressures, so nearly, that we may suppose it to be the result of 

 experiment ; while his allusion to the force of steam being sufficient to burst a 

 cannon, and his proposal of the method to a foreign prince, render it probable that 

 he was not a stranger to the volume the Marquis of Worcester had published 

 twenty years before. 



Morland's researches seem to have had little influence on the progress of the 

 practical application of steam. 



6. In 1695, Dr. Papin suggested the idea of employing the expansion and 

 contraction of steam to form a partial vacuum under a piston for raising water, and 

 making the pressure of the atmosphere on the upper side of the piston the moving 

 power. 1 The real authors of the atmospheric engine were very likely indebted to 

 this suggestion ; but neither Papin himself, nor his rival Savery, discovered how to 

 turn this suggestion to advantage. Indeed, it was proposed in a form which was 

 not practicable : the fire was to be alternately applied to, and removed from, the 

 cylinder, and the expansion of the water in it, by heat, was to raise the piston, and 

 its contraction, by cooling, when the fire was removed, was to cause a partial 

 vacuum, and, consequently, the descent of the piston was to be produced by the 

 pressure of the atmosphere. If such a scheme was ever tried, the result must have 

 been sufficiently discouraging for Papin to abandon it, and adopt a new one, which 

 it will be found he actually did, after seeing an engraving of Savery's engine. 



1698. THOMAS SAVERY. 



7. These projects were speedily followed by a direct practical application of the 

 steam engine to raising water, for which " letters patent " were granted to Captain 

 Thomas Savery, in July, 1698, (these being the first on record granted for a steam 

 engine) ; and, Dr. Robison says, it was " after having actually erected several 

 machines," of which Savery gave a description in a pamphlet he published in 

 1699, 2 called ' The Miner's Friend,' which was republished with additions in 1702. 



In June, 1699, Captain Savery exhibited a model of his engine before the Royal 

 Society ; and the experiments he made with it succeeded to their satisfaction. 3 It 



i Phil. Trans. Abridg. iv. 155. 1697. 



* Robison makes it 1696, but this does not appear to be correct. Switzen's date, 1699, is taken 

 as likely to be the right one, from his System of Hydrostatics, ii. 326. 

 3 Phil. Trans. Abridg. iv. 198. 1699. 



