Part 38 (1/2)

740 _Q_--Will the unbroken engine, in the case of disarrangeines of a screw or paddle vessel, be able of itself to turn the centre?

_A_--It will sometimes happen, when there is ine, on being started, cannot be got to turn the centre if there be a strong opposing wind and sea; the piston going up to near the end of the stroke, and then co able to turn the centre In such cases, it will be necessary to turn the vessel's head sufficiently from the wind to enable soot upon the vessel the engine will begin to work properly, and will continue to do so though the vessel be put head to wind as before

741 _Q_--What should be done if a crack shows itself in any of the shafts or cranks?

_A_--If the shafts or cranks crack, the enginethe vessel into port; but if the crack be very bad, it will be expedient to fit strong blocks of wood under the ends of the side levers, or other suitable part, to prevent the cylinder bottoive way The same remark is applicable when flaws are discovered in any of the ine, whether they be malleable or cast iron; but they inesfurther Should fracture occur, the first thing obviously to be done is to throw the engines out of gear; and should there be h on the vessel, the steam should at once be thrown on the reverse side of the piston, so as to counteract the pressure of the paddle wheel

742 _Q_--Have you any infors?

_A_--A very useful species of oil cup is now employed in a number of steam vessels, and which, it is said, acco of oil, at the sas A ratchet wheel is fixed upon a little shaft which passes through the side of the oil cup, and is put into slow revolution by a pendulu it lifts up little buckets of oil and e Instead of buckets a few short pieces of wire are so wheel, the drops of oil which adhere on rising froh part set upon the funnel, and which, in their revolution, the hanging wires touch By this plan, however, the oil is not well supplied at slow speeds, as the drops fall before the wires are in proper position for feeding the journal Another lubricator consists of a cock or plug inserted in the neck of the oil cup, and set in revolution by a pendulum and ratchet wheel, or any other , which is filled with oil when that side is upperh the bottom pipe when it co causes of the heating of bearings?

_A_--Bad fitting, deficient surface, and too tight screwing down

Someti the oil fro will becos heat froroove on the top brass for the distribution of the oil, the effect of which is to leave the top of the bearings dry In the case of revolving journals the plan for cutting a cruciform channel for the distribution of the oil does not do e; but in other cases, as in beam journals, for instance, it is most injurious, and the brasses cannot herever the plan is pursued The right way is tothe brass where it , so that the oil hest point of the journal, leaving the force of gravity to send it doard This channel should, of course, stop short a se of the brass, otherwise the oil would run out at the ends

744 _Q_--If a bearing heats, what is to be done?

_A_--The first thing is to relax the screws, slow or stop the engine, and cool the bearing ater, and if it is very hot, then hot water may be first eled is then to be adain cautiously tightened, so as to take any ju too slack The bearings of direct acting screw engines require constant watching, as, if there be any disposition to heat reat rapidity fro of a direct acting screw engine should have a cock of water laid on to it, whichoccur; and it is advisable to work the engine constantly, partly ater, and partly with oil applied to the bearings The water and oil are mixed by the friction into a species of soap which both cools and lubricates, and less oil moreover is used than if water were not employed It is proper to turn off the water soine is stopped, so as to prevent the rusting of the bearings

MANAGEMENT OF LOCOMOTIVES

745 _Q_--What are the chief duties of the engine driver of a locomotive?

_A_--His first duties are those which concern the safety of the train; his next those which concern the safety and right ine driver's first solicitude should be relative to the observation and right interpretation of the signals; and it is only after these demands upon his attention have been satisfied, that he can look to the state of his engine

746 _Q_--As regards the engine and boiler, what should his ineer of a locoine, so that the regulator, the whistle or the reversing handle may be used instantly, if necessary; he must see that the level of the water in the boiler is duly maintained, and that the stea the boilers ater, and the furnaces with fuel, a good deal of care and soularity in the production of steah the water be maintained at a uniform level; and an excess of water will of itself occasion prier The engine is generally furnished with three gauge cocks, and water should always coe cock, and stea: but when the engine is at rest, the water in the boiler is lower than when in ine is at rest, the water will be high enough if it just reaches to the enerate stealed stea with cold water the level at first falls; but it rises on opening the safety valve, which causes the steaer volume In locoeneration of steam is terear, if the engine has one, should be adjusted to the load, and the blast pipe should be worked with the least possible contraction; and at stations the damper should be closed to prevent the dissipation of heat

747 _Q_--In starting from a station, what precautions should be observed with respect to the feed?

_A_--In starting fro inclined planes, the feed water is generally shut off; and therefore before stopping or ascending inclined planes, the boiler should be well filled up ater

In descending inclined planes an extra supply of water may be introduced into the boiler, and the fire may be fed, as there, is at such ti inclined planes the regulator must be partially closed, and it should be entirely closed if the plane be very steep The same precaution should be observed in the case of curves, or rough places on the line, and in passing over points or crossings

748 _Q_--In approaching a station, how should the supply of water and fuel be regulated?

_A_--The boiler should be well filled ater on approaching a station, as there is then steam to spare, and additional water cannot be conveniently supplied when the engine is stationary The furnace should be fed with small quantities of fuel at a time, and the feed should be turned off just before a fresh supply of fuel is introduced The regulator may, at the same time, be partially closed; and if the blast pipe be a variable one, it will be expedient to open it widely while the fuel is being introduced, to check the rush of air in through the furnace door, and then to contract it very much so soon as the furnace door is closed, in order to recover the fire quickly The proper thickness of coke upon the grate depends upon the intensity of the draught; but in heavily loaded engines it is usually kept up to the bottom of the fire door Care, however, must be taken that the coke does not reach up to the bottom row of tubes so as to choke therate like a vault; and if the fire box be a square one, it is heaped high in the corners, the better to maintain the combustion

749 _Q_--How can you tell whether the feed pu properly?