16 
THE CORNISH PUMPING ENGINE. 
all such duties, upon proof by oath made before the customer or collector of the said duties 
(which oath he is hereby impowered and required to administer) that such coals have been so 
used and applied, which draw-back of all the said duties shall be returned and paid by the 
collector of the said duties, to such person so making proof as aforesaid.” 
22. The beneficial effect of this remission of the duty was immediately manifest, 
for the atmospheric engines were forthwith introduced in great numbers. Many 
mines which had been given up for want of adequate means of drainage, were 
enabled to be worked deeper, and new ones were opened in situations where, before, 
it would have been impossible to drain them. 
We now find mention of the existence of the engines in many quarters. 
Borlase, whose work 24 was published in 1758, informs us that many engines were 
in use at the time he wrote. He instances one at Pool mine, in 1746, having a 
cylinder 36 inches diameter “ from the outer edge;”—one at Ludgvan Lez work, in 
the parish of Ludgvan, of 47 inches bore;—one at Herland, in the parish of 
Gwinear, with a cylinder of the large size of 70 inches diameter;—and mentions 
“ several other very considerable mines which were worked by the fire engine, in 
the county, some of them having two engines to a mine.” He observes, that “ few 
mines were subject to more water than this engine would master; the only objec 
tions to it being the great expenses in erecting, and vast consumption of coals in 
working it. ” 25 
From Pryce 26 we learn, that within thirty-six years after the remission of the 
duty, above sixty engines had been erected in the county; and such an impulse had 
their use given to mining operations, that more than half of these had been rebuilt 
of more powerful dimensions, or had been enlarged in the diameter of their 
cylinders, to suit the increased depth of the mines. 
We also find on record, in reference to this part of our history, that Mr. Smeaton, 
who was in Cornwall in 1770, made minutes of eighteen large and powerful engines 
he saw there, eight of which had cylinders between 60 and 70 inches diameter. 
The principal makers of the atmospheric engines in Cornwall during this period 
were Jonathan Hornblower, the elder, and John Nancarrow. 27 
23. As soon as the fire engine came into general use, and was found to be an 
efficient and practicable method of draining the mines, attention became directed 
24 * The Natural History of Cornwall/ by William Borlase. Oxford. 1758. 
25 Pp. 170 to 173. 
26 Mineralogia Cornubiensis, p. xiv. 
27 Both these manufacturers were natives of Devonshire, and were supposed to have been introduced 
into the county by Newcomen. Nancarrow (or Nuncarrow, as the name is sometimes spelt,) subsequently 
emigrated to America, and settled in Philadelphia.