1850.] 



2. Metal as No. 1 bar. 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



199 



3. Metal shade lighter than No. 1 and 2 

 bars. 



Mean breaking weight of tlie three bars, 822 lb. 

 XVI. Mixture for Railwaij Chairs, 

 ^thpart Crmoshaij, No. \—Cold Blast. 



^part Redsdale, No. Z—Hot Blast, 

 ■^rdpart Scotch, No. 1 and Ti— Hot Blast. 



r 



I. Dark grey; uniform texture. 



2. Metal dull grey, as above; close and 

 uaifurm. 



406 

 51S 

 630 

 0S6 

 742 

 798 

 826 

 +854 

 BOdI 



406 

 518 

 630 

 686 

 742 

 708 

 826 

 +854 

 B944 



3. Metal as No. 1 and 2 bars 



406 

 518 

 630 

 686 

 742 

 798 

 826 

 854 

 +882 

 B889 

 Mean breaking weight of the three bars, 928 



{ 



•27 



■35 



■4 35 



■485 



•54 



•60 



■ma 



•655 

 •77 



•27 



•36 



•455 



•51 



•56."> 



•6i5 



•66 



•69 



•80 



•295 



•38 



•48 



•535 



•595 



•035 



•665 



■685 



•715 



•72 



lb. 



•012 

 •02 

 •03 

 •04 



•017 

 •02", 

 •035 



•U5 



•015 

 •035 

 •04 

 •05 



REGISTER OF ME-VIT PATENTS. 



STEAM BOILERS. 



William Edward Newto.v, of Chancery-lane, Middlesex, civil 

 engineer, for "(m invention of certain imjirovenients in steam 

 boilers." (A communication.) — Granted August 23, 1849; En- 

 rolled February 23, 1850. [Reported in Newton's London Journal.} 



The annexed engraving represents, in longitudinal vertical sec- 

 tion, a boiler constructed according to the present invention; a, 

 the fire-place; i, the fire-bars, surrounded by a wall of fire-bricks 

 c, built upon a ledge or platform /), made of sheet or wrought-iron, 

 and set in the masonry. The wall of fire-bricks thus forms a kind 

 of shallow well, the bottom of which is formed by the fire-bars b. 

 Fuel is supplied to the fire-place through an opening in front. The 

 upper part e, of the fire-place, where the heat from the fuel is de- 

 veloped, is made conical, with an aperture at the top for the escape 

 of the non-combustible gases up the flue /. The water of the 

 boiler surrounds this conical fire-chamber and vertical flue; and 

 the effect of this arrangement is, that the greater portion of the 

 rays of heat, which radiate from the incandescent fuel, impinge 

 against the sides of the cone, and are absorbed by the water which 

 surrounds the same; while the rest are reflected back upon the 

 fuel, and the heat in the fire-place is thereby very considerably in- 

 creased; so that, as the combustible gases are evolved from the 

 fuel, they are immediately consumed, instead of passing into the 



flue or chimney and escaping uselessly into the atmosphere. The 

 conical chamber e, and the flue /, leading therefrom, the inventor 

 prefers to construct of sheet copper, — that metal being a much 

 better conductor of heat than iron, g, is the outer casing of the 

 boiler, made of sheet-iron, and surrounded on all sides by a bed of 

 sand, or other bad conductor of heat, for the purpose of preventing. 



as far as possible, loss of caloric by radiation. The boiler is, hy 

 means of a supply-pipe A, kept nearly full of water, as shown; and 

 the steam that is generated in the boiler passes therefrom throutch 

 a pipe A-, into the steam-chamber i, wherein any water that may 

 come over with the steam will be deposited; and only dry steam 

 will be allowed to pass from the upper part of the vessel », down 

 the steam-pipe y, to the engine. The steam-chamber i, is furnislied 

 with a safety-valve A', and the upper end of the flue or chimney /i 

 is provided with a throttle-valve, for the purpose of regulating the 

 draft. Air, to support combustion, is supplied by the pipe /, to the 

 ash-pit, where it becomes warmed before it acts upon the fuel. 

 \Vhen it is requisite to remove the conical chamber e, and copper 

 flue./", and replace these parts by new ones, the top or cover <;', of 

 the boiler is first removed; the base of the cone e, is then detached 

 from the cast-iron platform p, and the feeding aperture rf, from the 

 sides of the vessel g\ after which, the flue /, and conical chamber 

 e, are free to he lifted out, without deranging or displacing any- 

 thing else, and a new chamber e, may be readily adapted to the 

 boiler. 



In order to set forth with clearness the nature of his improve- 

 ments, the inventor makes the following observations on the prin- 

 ciple of the generation of steam: — "It is based," he says, "upon 

 the difference in density or temperature of two bodies — viz., the 

 incandescent fuel and the water, which have always a tendency to 

 balance themselves or maintain an equilibrium. Thus, in order to 

 maintain a given expansive force of steam, certain conditions are 

 necessarj- — viz., first, the combustion of a given quantity of fuel in 

 the fire-place; second, a certain temperature of the fluids in the 

 flue or chimney must he maintained, dependent of course upon 

 the temperature required in the boiler; third, the metal, of which 

 the inner parts e, and /^ of the boiler are constructed, and which 

 transmit the caloric from the fire to the water, must be one of 

 the best conductors of heat, and he placed in a condition to con- 

 duct the heat as quickly as possible from the fire to the water; and 

 fourth, the metal of which the outer part of the boiler is con- 

 structed should be preserved as much as possible from radiating or 

 conducting away the caloric. The above conditions are necessary, 

 because the volume of steam will correspond to the volume or 

 quantity of fuel employed; and upon the temperature maintained 

 in the chamber e, aiul "chimney /, will depend the rapidity with 



