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THE PRIZE ENGINE AT CARDIFF. 



DESCRIPTION of the construction 

 A. ^ and manufacture of Messrs Clayton 

 &- Shuttleworth's portable engine (which 

 carried off the first prize in its class in the 

 trials at Cardiff) was given lately in Engineer- 

 in:^. The engine, it is stated, is of a 

 type introduced many years ago by Messrs 

 Clayton «S: Shuttleworth, the cylinder, which 

 is, of course, steam-jacketted all over, being 

 placed in the upper part of the smoke- 

 box, so that the exterior of the jacket is 

 exposed to the hot gases passing off to the 

 chimney. This arrangement is, we consider, 

 an excellent one, as it causes some of the 

 heat taken up from the jacket to be supplied 

 from the escaping products of combustion, 

 while the intervention of the jacket between 

 the hot gases and the cylinder proper pre- 

 vent any chance of the latter being over- 

 heated, so as to cause cutting. In the engine 

 we are describing the cylinder is lined with 

 steel; this lining, however, not being a regular 

 steel bush, such as is employed by the Read- 

 ing Iron Works Company, but being simply 

 a steel plate bent round so that the longitu- 

 dinal edges, whi(.:h are planed, butt fairly 

 together. The lining thus made is forced 

 into the cast iron barrel of the cylinder, the 

 latter being cast in one piece with the jacket, 

 as usual ; whereas, in the Reading Iron Works 

 Company's arrangement, the steel bush 

 actually forms the barrel of the cylinder, and 

 is merely surrounded by the jacket. 



The distribution of the steam is effected 

 by a pair of short slide valves with expansion 

 \'alvcs on the back, these latter valves having 

 ];rc)jecting bars so cast on them that each 

 valve forms a guide for the other, as the 

 distance between tlie valves is altered by 

 turning the screwed spindle. The degree of 



expansion is under the control of the 

 governor, the latter, as it rises, turning the 

 valve spindle, and separatmg the two ex- 

 pansion slides so as to give an earlier cut off. 

 On the expansion valve spindle is placed a 

 small brass pulley, and round this is coiled a 

 cord which is led oft' over a small guide 

 pulley, and hangs down by the side of the 

 engine. At the end of this cord is a disc, on 

 which weights can be placed ; these weights, 

 by pulling on the cord, tending to turn the 

 expansion valve spindle in such a direction 

 as to increase the admission of steam. By 

 altering the weights just mentioned, the 

 engine can be adjusted to run at a certain 

 desired speed with different loads, and the 

 arrangement appeared to answer well at 

 Cardiff, although the loose weights are 

 scarcely fitted for general use. 



The crank-shaft is of steel and has three 

 bearings, the centre one being placed close 

 to the crank. The arms of the crank were 

 carefully fitted into two cast-iron discs carry- 

 ing the balance weights, so that the shaft 

 has the appearance of being fitted with a 

 disc crank. This arrangement of balance 

 weights is an excellent one, and is very well 

 carried out. The crank-shaft plummer blocks 

 are carried by wrought-iron brackets, these 

 brackets being made so that they can spring 

 freely to allow for the expansion of the 

 boiler, while the plummer blocks are con- 

 nected direct to the cylinder by tie rods as 

 shewn, these rods taking the strains due to 

 the working of the engine. 



The feed pump, which is remarkably small, 

 but which is a beautiful piece of work, 

 delivers the feed into a feed-heater arranged 

 in the smoke-box, this heater being a casing 

 of horseshoe form, traversed from end to end 



