THE FELL ENGINES.

Evening Star, Issue 4293, 29 November 1876, Page 4

THE FELL ENGINES.

! Last week the Full engine, specially conI strueted for the steep gradients in the Pdmatuka tunnel, on the Wellington-Atasterton line, made a trial trip with satisfactory xcsults, which are thus described by the ' Post.' The special feature of this engine | is the duality of the machinery, it being, in 1 fact, two engines in one, not placed end to j end like the Fairlie double-bogie locomotives, but " mixed up " as it were, the cylinders and machinery for driving the ordinary j vertical wheels being placed outside, while | the other pair of cylinders working the hori- ! zontal wheels, which grip the third or central | rail used in steep gradient?, are inside. Doth : engines work quite independently, as Mas ' proved by driving both at full speed in opposite .directions. I here is a most ingenious c<>i:- ! trivance—the sand distributor—for blowing ; a jet of sand by steam on the central rail to , "grip" of the horizontal wheels, j the pressure of which is shown by another j skilful contrivance (the "pressure indi- | cator ") attached to the powerful screw brake j used to bring the wheels on both sides foroi- | bly against the middle rail. The engine literally swarms with marvellous new appli- | auees for diminishing LUx.r ;md increasing i efficiency, including an "injector " on a novel | principle for throwng water into the boiler j from the tanks. The total weight of the , engine is_ no less than thirty-three tons. So excessively complicated is the machinery that the makers—the Avonside Company, Bristol—deemed it necessary to send out a mechanical engineer expressly from England to put it together, not supposing that anybody in New Zealand could even attempt such a feat. This, however, was not only attempted but accomplished by Air Allison Smith, the general manager of the railway who, although he had never before seen one of these engines, put together the first of those landed here without the slightest hitch, To give an idea of the difficulty, we may mention that the machinery of each engine is in no fewer than 8,000 separate pieces, every one of which, of course, must go exactly in its proper place. Subsecpiently xMr Charles Hirst, the mechanical engineer referred to, arrived, and put together the other two engines. On the trial trip a start was made, with a pressure ef 125! bs of steam. The machinery worked with admirable smoothness, the slight stiffness at first noticeable speedily wearing oil'. It should be mentioned hero that° the' Fell engine is not intended for high speed, but expressly for drawing heavy loads up inclines, which it will do at the rate of eight to ten miles per hour, when the ordinary engines would slip helplessly down the hill. It can travel, however, at fair speed if required, on level ground, but the rails on the Hutt line are too light for its weight, bein« oidy about 401bs to the yard, whereas it is designed for 70 or SOlb rails, such as will be laid on the heavy gradients. It was therefore deemed inexpedient to put it to full speed during the trip. Asain, it must be remembered that the "Fell engine is not mounted like the Fairlie on a bogie carriage for rounding short turns, thus the sharp curves on the Hutt line formed a severe test. The first curve beyond Pipitea was rounded very steadily, at a speed of ten miles per hour, only a trifling creaking being perceptible, while the vertiealjvibration caused by the lightness of the rails diminished materially after the lirst few yards. The speed was increased to twelve and then to fifteen miles an hour, the steadiness of the running seeming to increase pari, passu with the velocity, which was augmented to seventeen miles an hour on the straight run befoic Kaiwarra bridge, which was reached in four minutes from Wellington. Here the lirst stoppage was made and the engine carefully examined, the inspection proving wholly satisfactory, not even ihe slightest heating of the radial axles being observed. On the straight run to the Lower Hutt the engine was tried at a speed of twenty miles per hour, the successive quarter miles beiii" done in seventy, sixty, iifty-five, fifty, and forty-five seconds. .Nothing could exceed the smoothness and steadiness with which the machinery worked, not the slightest lateral oscillation being perceptible. The ease with which the ponderous machine was started and stopped was shown by its being moved exactly any distance named, even to a few inches, I