Improvement in Steam Engine Boilers. 1 1 



and are inflammable on coming in contact with flame or fuel at a red 

 heat, such as anthracite coal well ignited. 



I make the said receiver, or generator of the vapor, of a suitable 

 form and size to receive the combustible fluids ; and with surface 

 enough for the air to pass over to take up and receive its charge, 

 when it is led by a pipe to the furnace ; and when circumstances 

 permit hot and dry air to be admitted, it will take up the vapor more 

 freely. 



The introductory pipe or pipes, must each have a cock, not far 

 from the furnace, to govern the supply ; and between the cock and 

 the furnace, a wire-gauze screen, on the principle of the safety lamp 

 of Sir Humphry Davy : and to keep the same free from obstruction, 

 I sometimes cause a small stream of steam, led from the boiler, to 

 enter behind the screen of wire gauze, and strike it in the direction of 

 the course of the current of vapor continually or occasionally, and with 

 the more sure advantage when the temperature is high, and the pipe 

 prolonged in the furnace very hot ; when some additional portions of 

 hydrogen may be obtained from its decomposition. 



The boiler of the engine, when this auxiliary fuel is to be used, 

 should be made with proper adaptation to this intention. Whatever 

 the size or form of the boiler, the bottom of the furnace will be oc- 

 cupied with a narrow grate of coal. When the boiler is made of 

 four long cylinders, in ' the manner of my anthracite coal furnace- 

 boiler, then this improvement thereon can be conveniently applied ; 

 the introducing tubes being so arranged as to direct the vapor upon 

 or into the most Hvely part of the fire. When the boiler is for loco- 

 motive engines, the furnace will be more conveniently placed in an up- 

 right cylindrical boiler, with a reverberatory roof or dome within, that 

 will be covered with water ; the flue leading into a long horizontal 

 part, or into other upright divisions of the cylindrical boiler, till the 

 heat is principally imparted to the water. 



But as the flame thus produced, demands a large supply of oxy- 

 gen from the atmosphere, and if it were received wholly through the 

 grate, it might not only cause the coal to consume disproportionably 

 fast, but the air be deficient in oxygen, I supply it by means of 

 air tubes around the furnace, with convenient stopples or stop cocks, 

 to regulate the quantity, and wholly stop it when anthracite coal alone 

 is used ; the air tubes in passing in, contracting to a small orifice to 

 increase the velocity of the air — an exhauster of the funnel Qr chim- 

 ney, a fan wheel, as usual, operating to increase the draft. 



