120 REPORT--1853. 



On an improved Patent Steam- Engine Boiler desir/nated the Greatest i?e- 

 sistance Steam-Boiler. By Joseph Hopkinson, Engineer, Huddersfield. 



The boiler is a combination of three circular boilers laid horizontally to form the 

 furnace. The two side boilers or generators, forming the fire-box, are each 4 

 feet in diameter. The upper boiler is of the same diameter, with a dome at the 

 end forming a reservoir for steam. There is also an inverted dome ; to this part of the 

 boiler the sediment settles, and is blown out. The action of the flame from the 

 furnace is diverted by the inverted dome towards each side boiler, and made to enter 

 the tubes. Each side boiler is provided with seventy-five tubes 3 inches in diameter. 

 The length of each side boiler is 8 feet ; the upper boiler is longer than the side 

 boilers by the diameter of the dome. The front end of the upper boiler is egg- 

 shaped, and projects past the side boilers the length of the egg end, making the 

 extreme length of the upper boiler 14 feet. The centre boiler with the dome forms 

 the principal steam-chamber ; and the form gives plenty of space for this purpose, 

 thus preventing to a great extent that priming to which boilers with contracted 

 steam room are much subject. 



The space occupied by this boiler in width is 11 feet 3 inches, and its height from 

 the floor to the upper surface, exclusive of the dome, is 6 feet ; the width of the 

 furnace is 4 feet 6 inches, and the length of the grate-bar 6 feet ; making the area 

 of the grate surface 27 superficial feet. The effective heating surface of the fire-box 

 and boiler, independent of the tubes, is 140 superficial feet ; seventy-five tubes in 

 each boiler, of 3 inches in diameter and 8 feet long, gives 900 superficial feet of tube 

 surface ; and the total amount of fire-box and tube surface is 1040 superficial feet, 

 allowing 16 superficial feet of heating surface per horse power : this boiler, though so 

 small of itself, will be sixty-five horse power. 



The largest diameter being 4 feet, if made of :J-inch plate, is equal in strength to 

 a 6-feet boiler made of f -inch plate, and equal to a boiler 8 feet in diameter made 

 of ^-inch plate ; the whole weight, including the 150 tubes, will not exceed five tons. 

 The advantages to be derived by the use of such a boiler are, that the form and 

 combination allow of simple construction, and avoid complication ; no angle irons 

 or stays are required; small diameters are placed in such a position as to form 

 a large fire-box. Each part is separate and easily connected or disconnected. Any 

 single part can be removed without injuring the other parts ; and any one part can 

 be replaced with a new portion, independent of the other portions, for transit to any 

 part of the world : this boiler offers peculiar advantages, as a powerful boiler may 

 be conveyed in separate portions, and put together with little trouble. Another 

 advantage in this construction of boiler, is a large furnace, consequently the stoker 

 is enabled to place large quantities of fuel in the furnace each time he fires ; thus 

 the doors may be kept closed longer than with ordinary firing, thus preventing 

 cold air from entering the tubes, a very important consideration with tubular boilers. 

 A large furnace also affords unusual facilities for smoke consuming. Another im- 

 portant feature is, the first cost is considerably reduced. 



For marine purposes, with slight modifications, this boiler presents many advantages; 

 the principle of true construction will enable the expansive piinciple to be further 

 carried out in marine engines, and thereby reduce the consumption of fuel. For 

 war steamers these boilers can be so constructed, that should any single part become 

 damaged, it could be shut off from the other, allowing the full power of the remaining 

 portions to continue. 



The small space occupied in the height with this boiler, would also be of advantage, 

 it being considerably below the water-line of a war steamer. 



A brief Description of Locking atid Cook's Patent Potatory Valve-Engine^ 

 and of its Advantages. By George Locking, Hidl. 



Tlie principal feature in this engine consists in one valve doing the work of two 

 slide-valves and with fewer rubbing surfaces. All eccentrics, levers, &c. are dispensed 

 with. The valve is placed between two ordinary rectilineal cylinders, and the rotatory 

 motion is eflected by means of bevel gear fixed to the crank-shaft and valve-spindle; 

 the pinion on the crank-shaft being to the bevel-wheel on the spindle in the propor- 



