M I N E. 



359 



Minesof the barrel produces an ascent of 13 yards. In short, 

 Caul. there seems almost no limitation to the execution of 

 i^ ,-nJ ^orfc by these engines. For all great outputs of coal, 

 Brewing Watt's engine is in the most general use. The mo- 

 " Uu| ' tbe raentum of these machines is so great, and the fly- 

 '"'*' wheels are so heavy, and go at so great a velocity, that 



the mere suspending of the moving principles of the 

 engine would not stop the movements at the instant 

 wanted, on which account a very powerful brake is ap- 

 plied to the periphery of the fly-wheel, or rope-barrel, 

 to that the brakeman, by applying his foot to the re. 

 gulating lever of the brake, while, with his hands he 

 huts the valves of the engine, can pitch the corve and 

 expend its rapid motion within a few inches of the re- 

 quired height at every delivery. 



Many attempts have been made to apply the steam- 

 engine to an endless chain or chains suspended from 

 the top to the bottom of the pit. Several are in use, but 

 it is questionable how far they are applicable to very 

 deep pits ; as they have hitherto been only applied in 

 ptts of moderate depth. The best principle we have 

 een, is that invented by Mr. Hiiijh Baird, civil engi- 

 neer, and applied in practice at the Shott* Iron Work, 

 which, though on a small scale, shews the effect most 

 correctly. Two endlew chains having long stave 

 links, are suspended from two barrels placed over the 

 mouth of the pit. The diameter of the barrel* is more 

 than double the depth of the hutch ; and to keep the 

 chains regular, they pas* under other barrels beneath 

 the scaffold of the pit bottom ; studs of iron project 

 from the imide of each chain, at regular distances, ac- 

 cording to the power of the engine, and the hutches 

 have ears of iron, by which they ire supended on the 

 tads of the chain. Upon the end of the chain-barrel 

 is a toothed wheel, into which a pinion works, placed 

 on the fly-shaft of the engine. The chains have guides 

 to prevent them going off the barrels, and there are 

 ktu'N on the barrels which enter into the links, and 

 prevent the chains slipping round, so as to keep tlie 

 studs upon the sides of the chain, exactly opposite and 

 parallel. When the engine is set in motion, the chains 

 ascend on one side and descend on the other. The 

 loaded hutches, as they come to the pit bottom, are 

 set forward, till the ends of them, having the iron ears, 

 are in a line with the perpendicular of the ascending 

 chain, the studs of which catch the ears and carry the 

 hutch up the pit, which passes over the axle of the 

 chain-barrel, and is set down on the strike-boards at 

 the side of the pit. The empty hutches are attached 

 in the same manner at the ascending side of the chains 

 at the pit-mouth, go over the barrel, and descend to 

 the bottom. For attaching the empty hutches and de- 

 taching the loaded ones, there are moveable strike- 

 boards, which are wrought by a mechanism attached 

 to the machinery. The execution of this machine is 

 very considerable with an engine of moderate powers, 

 as the engine never stops from the beginning to the 

 end of the day's work. Plate CCCXCIV. Fig. 11. 

 eoxuv. ihewt the hutch passing over the axle at the pit top. 

 I if. 11. T(,e other kinds of machines are those where water 



is the moving power. The oldest and most simple is 

 a water-wheel, or rather two water-wheels joined to- 

 gether by the sides, the buckets set reverse to each, so 

 that when water is applied on one side of the wheel, 

 the wheel turns forward, and when applied on the 

 oilier side it turns backward. To the axle of the wheel 

 a rope-barrel is attached, or a second power may be 

 produced, by a pinion and wheel as in the steam en- 

 gine. 



Mines of 

 Coal. 



The other kind of water engines for drawing coals, 

 is strictly applicable only in pits level free, where the 

 ascent of the loaded corve is produced by a descending 

 cassoon filled with water. When the ascent and descent CO a )4U p ,t, c 

 of both are equal spaces, then the rope-barrel for the P J U . 

 cassoon and for the corves are of the same diameter ; but 

 when the pits from where the coals are drawn, are 

 deeper than the point of discharge for the water into 

 the dry-level, then the cassoon is made large, and its 

 rope-barrel much smaller than the barrel for the corve- 

 rope, so that by the time the cassoon reaches the half 

 depth, for example, the corve may have ascended 

 double the depth. The cassoon is filled by a valve at 

 the pit top, and upon its reaching the place for dis. 

 charging the water, a self-acting valve lets it off'. The 

 loaded corve is taken off at the pit head, and the de- 

 scending rope and empty corve, pull up the cassoon 

 with ease, on account of its being suspended from a 

 barrel much less in diameter. All the motions of this 

 machine, which would be very variable and destruc- 

 tive, if left to itself, are regulated by a very powerful 

 brake at the pit top. 



As much cool and many corves are destroyed by the 

 corves striking at the meetings, where the ascending 

 and descending velocity together is r<jual in some 

 cases from 90 to SO feet per second, various plans have 

 been devised to obviate this loss. One of the simplest 

 plans is to divide the pit from top to bottom, so that 

 each corve has a distinct pit for itself. 



A second mode was invented by Mr. John Curr, 

 Sheffield, which was to have guides of wood attached 

 from top to bottom of the pit ; these are long pieces, 

 or spo.irs of fir wood, about four inches square, at- 

 tached perpendicularly to the sides of the shaft, and 

 to buntons in the middle of the pit. Betwixt these 

 guides, sliders with friction-rollers are placed, attach- 

 ed to the gin-ropes, and to these sliders the corves are 

 suspended. By this plan the corves or hutches can be 

 drawn with great velocity ; but there is a considerable 

 hinderance in striking, or banking the corve at the 

 pit top, as shutters or sliding boards have to be used. 

 This plan is not applied in the Newcastle practice, 

 but is highly beneficial where large coals have to be 

 raited. A third mode, of a simple form, is to suspend 

 four chains from the pit-head frame, or round rods of 

 iron screwed together in pieces of 12 or 15 feet each ; 

 these are fastened to a strong beam or cill at the pit 

 bottom, and are kept tight by a regulating tcrew at 

 the top. The slider used for the chains or iron rods, 

 is Jouble-eyed bolt or rod. Though these are in 

 practice in pits of moderate depth, they are never ap- 

 plied in pits of a great depth. 



In drawing coals, both ropes and chains are em- 

 ployed. 



The round ropes are shrowd laid ; and the best are Dof . 

 tbosie made upon the correct mfchanicid princ i 

 invented liy Mr. Chapman end Mr. lluddart, nil the 

 yarns being laid equally, so a* to have uniform tension 

 wht-n the strain is applied. 



The other kind of rope is known by the name of the 

 flat rope, which is without doubt the best of any yet 

 invented for drawing coals, and has proved an im- 

 mense aving compared with round ropes. They are 

 made of four ropes laid horizontally together, and ar 

 alternately right and left laid ropes. My this very in- 

 genious plan, the ropes counteract each other in the 

 twist, and hang like a ribbon down the pit; they arc 

 connected or sewed together by a small rope, which 

 operation requires very powerful machinery to pierce 



