236 Literary and Philosophical Society. 



the flame has passed through the burning fuel, I cause it to 

 pass through a very hot tunnel, flue, or oven, before it 

 comes to the bottom of the boiler, or to the part of the 

 furnace where it is proposed to melt metal, or perform 

 other office, by which means the smoke is still more 

 efl"ectually consumed. In other cases I cause the flame to 

 pass immediately from the fire-place into the space under 

 a boiler, or into the bed of a melting or other furnace.' 

 He varied the figure or form and proportions of the fire- 

 places, &c., but in all cases the principle was the same ; 

 the fresh or raw fuel being placed next to the external air, 

 and so that the smoke or flame passed over or through the 

 coked or charred part of the fuel. 



' Secondly,' he goes on, ' in some cases I place the 

 fresh fuel on a grate as usual, and beyond that grate, at 

 or near the place where the flame passes into the flues or 

 chimneys, I place another small grate, on which I main- 

 tain a fire of charcoal, coke, or coals which have been 

 previously burnt until they have ceased to smoke ; which, 

 by giving intense heat and admitting some fresh air, 

 consumes the smoke of the first fire. 



' Lastly, be it remembered,' he concludes, * that my 

 said new invention consists only in the method of con- 

 suming the smoke and increasing the heat, by causing the 

 smoke and flame of the fresh fuel to pass through very 

 hot tunnels or pipes, or among, through, or near fuel 

 which is intensely hot, and which has ceased to smoke, 

 and by mixing it with fresh air when in these circum- 

 stances ; and in the form and nature of the fire-places 

 herein mentioned, described, and delineated ; the boilers 

 and other parts of the furnaces being such as are in 

 common use. And be it also remembered, that these 



