166 president's address. 



cylinder of nearly four feet in diameter and its performance was 

 regarded as extraordinary since it made fifteen strokes a minute 

 and drew up at each stroke about a hogshead of water from a 

 depth of 180 feet. 



The cost in coal was very great but it saved the mine and 

 made the beginning of the fortunes of Mr. "William Lemon who 

 afterwards removed to Truro and began working the Great 

 Q-wennap Mines on an extensive scale. This Mr. Lemon is the 

 founder of the great Cornish family so well known here. 



In 1725 another engine was erected at Wheal Rose near 

 Redruth, under the superintendence of Joseph Hornblower who 

 afterwards erected another at Wheal Busy, Chacewater, and a 

 third at Polgooth. 



Engines of Newcomen's pattern continued to be erected long 

 after Newcomen's death, till there was scarcely a tin or copper 

 mine of any importance in Cornwall that had not one or more of 

 such engines at work. 



Smeaton, the celebrated engineer, who brought this class of 

 engine to the highest perfection of which it was capable, erected 

 at Chacewater in 1775 the finest and most powerful that had 

 until then been constructed, having a cylinder 6 feet in diameter 

 and a maximum stroke of 9 feet 6 inches. But as Price, writing 

 in 1778, tells us in the appendix to his " Mineralogia Cornubi- 

 ensis" the vast consumption of coal of these engines, amounting 

 in cost to about £3,000 per annum, was almost a fatal drawback. 

 Still, in 1780 there were, as Smeaton informs us, eighteen large 

 engines at work in Cornwall, many of which were built by 

 Jonathan Hornblower and John Nancarrow. Of these men a 

 good deal is known, but biographers have altogether failed to trace 

 any personal history of Thomas Newcomen, the great inventor of 

 the steam engine. 



I shall again refer to the Hornblowers later, but we must 

 now pass to James Watt, the great magician who at a bound made 

 the real steam engine which worked, not by the pressure of the 

 atmosphere, which could never equal 15 lbs. to the square inch, 

 but by the power of the pressure of steam which is only limited 

 by practical considerations and is used to-day up to 1 50 lbs. and 

 often much more, per square inch. Watt's great invention includ- 



