CHAP. VI. 



TREVITHICK'S TRAM-ENGINE. 



83 



chimney. In fact, the waste steam seems to have been 

 turned into the chimney in order to get rid of the nui- 

 sance caused by throwing the jet directly into the air. ^ 

 Trevithick was here hovering on the verge of a great 

 discovery ; but that he was not aware of the action of 

 the blast in contributing to increase the draught and 

 thus quicken combustion, is clear from the fact that he 

 employed bellows for this special purpose ; and at a 

 much later date (1815) he took out a patent which 

 included a method of urging the fire by means of 

 fanners. 



TREVITHICK'S HIGH PRESSURE TRAM-ENGINE. 



At the first trial of this engine it succeeded in 

 dragging after it several waggons, containing ten tonsl 

 of bar-iron, at the rate of about five miles an hour. I 

 Rees Jones, who worked at the fitting of the engine 

 and remembers its performances, says, " She was used\ 

 for bringing down metal from the furnaces to the Old \ 

 Forge. She worked very well ; but frequently, from 

 her weight, broke the tram-plates and the hooks be- 

 tween the trams. After working for some time in this / 

 way, she took a load of iron from Pen-y-darran down the / 



G 2 



