M I N E. 



341 



MIMS of going down, the bucket in the working barrel pro- 

 C ** L gressively has its working space higher up. If die 

 '"""" working barrel is ten feet long, and the restricted 

 1 stroke of the engine six feet, and if tne bucket is at the 

 bottom of the barrel when the engine is ready to make 

 its stroke, then the pumps can be lowered about four 

 feet, ere the bucket be working at the top of the bar- 

 rel. To this descent of the pumps particular atten- 

 tion has to be paid ; and therefore, as soon as the pumps 

 have sunk four feet, the spears'and bucket are let four 

 feet lower into the barrel, and this is done at the top 

 of the pit when the spears overlap, and are fixed late, 

 rally by screwed glands. 



r olumr.i of The common depth for a set or column of pumps 

 being from 25 to 30 fathoms, when this depth is at- 

 tained by the first set, preparation must be made for 

 fixing the upper pit cistern, into which the upper set 

 of pump* is to be placed, and into which the water of 

 the second set is to be thrown. If a strong bed of sand- 

 stone is found, a curceroent is left of the rock pro- 

 jecting about three feet into the pit, and is formed, in 

 the course of sinking, into a chin or strong bracket, to 

 support that part of the cistern upon which the upper 

 set of pumps is to rest ; and a few feet under it, 

 the pit is formed into its regular width. A recess is 

 cut into the side of the pit backwards from the brack- 

 et, for holding the cistern into which the upper set of 

 pumps is to be placed. For the greater security of 

 the place where the pumps rest, the recess is formed 

 dove-tailed, about eleven feet back from the face of the 

 bracket, from three to four feet in breadth, and about 

 thirty inches in depth. Into this, a pit cistern bun- 

 ton is laid and firmly wedged, composed either of 

 oak or of best foreign redwood pine, having the thick 

 end laid into the back part of the recess, to prevent its 

 coming forward into the pit, by the concussions and 

 vibrations of the pumps, and in case of any failure of 

 the bracket under the pumps. The inner end of this 

 bunton is farther secured by blocks or chokes of wood 

 placed betwixt the upper side of the bunton and roof 

 of the recess ; similar chokes are placed upon the in- 

 ner end of the cistern. When the rock is of such a 

 quality as not to be fit for forming a bracket, then a 

 cross bunton of wood is substituted, from one to three 

 feet in breadth, and from two to four feet in depth, 

 according to the weight of the column of pumps to be 

 supported. This bunton is fixed into the sides of the 

 pit, and has a hold at each end from two to four feet, 

 according to the strength of the rock ; upon this the 

 rn is placed, having a recess as before described ; 

 sometimes logs eight inches thick are placed into the 

 recess, at right angles to the cross bunton, firmly se- 

 cured together, and upon these the cistern is placed. 



Although from 20 to 30 fathoms is the common 

 length of a lift or set of pumps, it sometimes is neces- 

 sary to make it much longer, when no 'place can 

 be found in the shaft for fixing a cistern, on account of 

 the tubbing ; from this cause a lift of pumps has been 

 made of 70 fathoms in length ; but this requires un- 

 common strength of every material, and such a length 

 is only made from absolute necessity. 



It ii the practice to use the sinking set of pmps for 

 linking the whole depth, so that as soon as the first 

 cistern is ready, a set of pumps, named a fixed set, is 

 substituted for the sinking set. In common practice, 

 fixed sets of pumps are joined together by flanges and 

 bolts, but in the improved practice, nil the fixed sets 

 have spigot and faucet joints ; and the joints are made 

 water-tight by tappings of tarred flannel. But the 

 lower set of pumps of every engine has flange joints, 



with strong bolts, for the special purpose of their being Mines of 

 connected in one firm column, so that if the water ' 



should grow up the pit, or any leak happen in them AT v r~ 



11 r r f u <* inn">K 

 below water, tae whole may be drawn up from the coa i.fi,id. 



bottom, if necessary, and repaired ; which operation 

 could not be effected with the other kind of joints, as 

 they would not hang together. In the case where 

 there is only one lift of pumps, the flange-joints are for 

 the same reason used. The spigot and faucet joints 

 render the drawing of pumps one by one, and placing 

 and jointing them, a much quicker operation than when 

 the other joints are used. In general, the Operation 

 may be performed in less than a tenth of the time re- 

 quired for the other kind ; and it may be frequently of 

 great service to have the upper half of the lower set with 

 spigot and faucet joints, if there is no risk of the water 

 rising very quickly up the shaft, of which there is ge- 

 nerally little danger after the colliery is opened up, 

 and a sufficient reservoir formed for the water. 



With regard to the mode of collaring the pumps in 

 the pit, keeping them steady, and in a true perpendi- 

 cular line, tne old practice is to have two buntons of 

 bout nine inches deep, and six inches in breadth, to 

 pass close to the side of each pipe under the flange 

 or joint The ends of these are fixed into the shaft wall, 

 and the other ends re.-t on brackets fixed to the brat- 

 tice wall ; the other sides of the pipe are collared by 

 pieces of wood, named rackings, and in some cue* 

 stretch only the breadth of the buntons ; or, if the pit 

 admits of it, one or both of them are fixed into the side 

 of the shaft wall. The improved plan, in order to give 

 as much room as possible for the operations which are 

 so frequently carried on in the engine pit where tin- 

 pumps are, is to fix a strong bunton under the joint of 

 each pipe ; to which buntons the pipes are firmly at- 

 tached by a collar of iron, with screws and nuts, as 

 represented Plate C ( i \( . Fig. 13. By this plan PL.T. 

 there is much more room in the pit cccic. 



Though tin's mode of fixing the pump* i* very suit- *' 1S " 

 able for all the upper sets of pumps, it is not so for 

 lower sets, where, from accidents -to which they are 

 liable, the pumps are sometimes to draw up bodi- 

 ly. The mode of fixing with buntons and racking* is 

 therefore preferred in the lowest et, and the fixtures 

 are so made, that if there is not time to remove the 

 buntons and rackings, the whole may be hove up. In 

 cases where the buntons hold fast, they must be cut 

 way under water by chiucls fixed upon loaded 

 pears. 



With regard to the water which is found in sinking Ringing of 

 through the several strata, in ordinary case* it is con- P"- 

 fiucted down the walls of the shaft. If the strata are 

 of a firm consistency, a hollow ring is cut into the 

 sides of the pit in a spiral line down the shaft, and 

 when the ring can hold no more water, the water is 

 either conducted down in square spout to the near- 

 est pit cistern, or groove is made in perpendicular 

 direction in the shaft wall, and square box either in- 

 serted into it, flush with the side* of the pit, or it is co- 

 vered with deal fitted tightly to the cavity. Similar 

 spiral rings are formed in succession downwards, and 

 the water conducted always into the nearest pit cis- 

 tern. 1'he improved plan is, to insert rings of wood 

 or cast iron, flush with the side* of the pit, and the wa- 

 ter is conducted from one ring to another, by mean* of 

 perpendicular pipes, until the under ring can hold no 

 more water. When the water from that ring is car- 

 ried in pipe* to the nearest cistern, then a new set of 

 rings is inserted under these, and the water conducted 

 in the same manner ail the way down. A* keeping 



