THE CORNISH PUMPING ENGINE. 
9 
subsequent inventors to fill up, and make them sufficiently complete to be put in 
execution. 
The character of originality which Savery’s engine bears, renders it highly pro 
bable that the whole of the design is his own; and if so, he is entitled to the credit 
not only of the discovery of the two great principles upon which the steam engine 
acts, viz. the expansive force and condensibility of steam, but of having invented a 
very complete, efficient, and useful machine for carrying them into effect,—arranging 
all the details with great skill;—conducting its manufacture on a large scale;— 
publishing and clearly explaining, without equivocation or mystery, its principles 
and construction to the world;—and bringing it successfully into public use. 12 
How few inventors can boast a character so deserving of honor. 
newcomen’s or the atmospheric engine. 
12. It is very probable that the failure of Savery’s attempts to introduce his 
engine into the Cornish mines, first prompted Newcomen, who resided at no great 
distance, and was in the habit of visiting Cornwall, 13 to turn his attention to the 
subject, and to perfect and put in execution the apparatus originally suggested by 
Papin in 1690. 
A glance at the admirable manner in which the atmospheric engine was rendered 
free from the objections to Savery’s plan, serves to strengthen this supposition. 
For, contrasting with Art. 10, we find, 
1st. Only one engine was required for a shaft, however deep; and this was 
placed in the most convenient situation possible, namely, on the surface of the 
ground at the mouth of the mine. 
2nd. Thus much less risk of stoppage from accident was incurred ; the engine 
was rendered independent of any extraordinary influx of water into the shaft; 
and its action could be continued without interruption until a complete drainage 
was effected. 
3rd. The use of steam higher than atmospheric pressure was not required: 
hence the danger of bursting was removed; and even if such an accident had 
12 This has been doubted, but passages in the ' Miner’s Friend ’ show that he had constructed several of 
his engines before that work appeared. Bradley, in the treatise already alluded to, refers to one engine 
as being “the truest proportioned of any about Londonconclusive evidence that many were then in 
existence. 
13 “Of all places in England, the tin mines of Cornwall stood most in need of hydraulic assistance; 
and Mr. Savery was much engaged in projects for draining them by his steam engine. This made its 
construction and principles well known among the machinists and engineers of that neighbourhood: 
among these was a Mr. Newcomen, an ironmonger or blacksmith, and Mr. Cawley, a glazier, at Dart 
mouth in Devonshire, who had dabbled much with this machine.”—Robison’s Mech. Phil. vol. ii. p. 57. 
C