44 On Gas Furnaces, 



blast furnace to calcine lime and burn bricks. In 1829, after 

 Reitron's discovery of the hot blast principle, the air-pipes 

 were heated in the flame of the furnace both in France and 

 England. In 1835, MM. Thomas and Laurens in France 

 applied the flame of the furnaces to heat the steam boilers 

 of the blowing machines; and in 1841, they made known their 

 success in applying the gas process to reverberatory fur- 

 naces in the iron works of Treveray. 



4. In India, I first became acquainted with the heating 

 powers of the gas principles in August 1842 ; in consequence 

 of the bamboos and ridge pole of the shed under which I 

 had placed my little experimental iron furnaces, having been 

 several times set on fire by the large volumes of flame 

 thrown up from a furnace hardly three feet high. To pre- 

 vent this, I had constructed a pillar chimney for the centre 

 of the shed, with a nine-inch flue, into which the flame 

 from the mouth of the furnaces was drawn up by the draft 

 through lateral apertures : when to my astonishment, I 

 found that in less than half an hour the whole flue was 

 heated red hot from top to bottom, for more than ten feet 

 in length, and a brilliant flame thrown out besides, from the 

 summit of the chimney, more than four feet high ; producing 

 in the shades of evening a beautiful fire-work, resembling 

 an immense " Gerbe," the sparks being afforded by the 

 powder of the charcoal drawn up. The discovery of the 

 different applications and mode of management of the gas of 

 course rapidly succeeded ; but although I was aware of the 

 use of Thomas and Laurens' blowpipe principle, and what 

 might be done with it, yet it was out of my power to try it 

 upon any scale larger than a small experiment. 



5. In Bengal, I consider the application of the gas furnace 

 of immense consequence, as it affords the means of readily 

 using the worst coals, now almost valueless to heat the steam 

 boilers of the boats employed on the inland navigation of the 

 rivers. Many other applications must also readily present 



