ENGINES FOR SOUTH AMEUICA. 211 



brick flues under the boiler, returning through the 

 tube. 



The cylinder for the winding engine was probably 

 fixed in the boiler, costing, with whim-barrel and wind- 

 ing apparatus complete and ready for work, 2LO. Does 

 the reader ask, Did so cheap an engine ever work ? Or 

 perhaps his knowledge of engineering gives rise to the 

 question, How did it work ? for it looks like a Newcomen 

 of just exactly a hundred years before, only it needs no 

 injection water or great main beam ; and certainly it is 

 not a Watt, for it has neither air-pump nor condenser, 

 nor vacuum, nor cylinder-cover, nor parallel motion, nor 

 any other thing like Watt invented; but it has high-pres- 

 sure steam, which he disapproved of, and it really worked 

 thousands of miles away, where there were no mechanics 

 to keep it in order, and on mountains so difficult of 

 access, and in so light an atmosphere, that Watt, who 

 had the first chance of supplying steam-engines to the 

 New World, declared it to be impossible. The pumping 

 engines are described in Trevithick's note of 22nd May. 

 They also were high-pressure puffer-engines with open- 

 top cylinder, 24 inches in diameter, 6-feet stroke, with a 

 cross-head working in guides, and side rods connecting 

 to the pump-rods. Two valves turned the steam on 

 and off from under the piston, with the ordinary gear 

 and handles. The boiler was similar to that for the 

 winding engine, but larger, and had not the cylinder 

 fixed in it ; a balance-beam regulated the movements, as 

 it had no great main beam, and differed from ordinary 

 engines just as the winding engine did. The power 

 was 33 horses, and with an 11-inch pump barrel, 

 150 feet of 11-inch pumps, a winch, and all apparatus 

 necessary for draining the mine, the cost was but 

 1400J. 



