10 VARIOUS INVENTIONS. 



means all the heat given by ignition would pass into 

 the steam, and his steam-puffer become an aerated 

 steam-engine. 



From- the following it appears that this plan of 

 Trevithick's is now coming into use as something quite 

 new : 



" In your last impression, under the head of ' Air and 

 Steam combined, as a Motive Power,' you state i the 

 invention was described to be that* of Mr. Warsop, but 

 we have recently heard that a few years back (1865) 

 the same invention had been protected in an earlier 

 patent than Mr. Warsop's, by Mr. Bell Galloway .' " l 



Trevithick thought of patenting a plan for reducing 

 copper ore by the use of a blast, in preference to the 

 usual air-furnace and chimney, but something similar 

 had been tried by Mr. Grould, and he therefore proposed 

 to erect a blast-furnace in Dolcoath Mine, receiving a 

 portion of the saving of fuel as his remuneration. Such 

 a furnace worked there for many years, until copper 

 smelting was removed from Cornwall to Wales. The 

 plans for a breakwater at St. Ives were for an under- 

 taking that has since been in many hands, but without 

 success, except perhaps for the convenient making of 

 members of Parliament. Some slight progress has been 

 made by engineers and contractors, but vessels are not 

 willingly taken to the port, and ratepayers grumble at 

 unprofitable harbour taxes. 



" DEAR TREVITHICK, " LONDON, January 20th, 1811. 



" I have not lost any time in mentioning your wishes 

 respecting a compensation for the plan of smelting copper to 

 Lord Dedunstanville, who intends mentioning the affair in his 

 next letter to Mr. Keynolds. Lord Dedunstanville wishes you 



1 See the * Mechanics' Magazine,' June 3rd, 1870. 



