A HISTORY OF CUMBERLAND 



not otherwise have been worked with safety. The 

 mine, which is liable to inrushes of sand and water 

 from the cover, is drained by three Cornish pump- 

 ing engines, each having a cylinder 70 inches 

 diameter by 9 feet stroke. One of these engines 

 works a plunger 25 inches diameter by 10 feet 

 stroke, the other two each work a pair of 1 8-inch 

 plungers by 10 feet stroke, all from a depth of 50 

 fathoms, with bucket lifts from 60 fathoms up to 

 the 50 fathom level. As a general rule one of 

 these engines is sufficient to keep the mine drained, 

 but when a run of sand occurs it takes two and 

 sometimes all three of them to contend with it. 

 The plungers lift sand and water with ease so long 

 as the sand is kept in a fluid state, and this is 

 effected by taking a jet of fresh water down from 

 the surface and discharging it into the sump, 

 which, acting under a head of 300 feet, keeps the 

 sand in the sump in such a condition of fluidity 

 that the plungers lift it without difficulty ; and 

 should the sand during a temporary stoppage settle 

 in the pump column, the door of the top clack is 

 removed, the jet is turned up the column, which 

 quickly clears it of sand, the door is then replaced, 

 the column is filled with fresh water from the top, 

 and the engine goes to work again at once. 



The winding engines are direct acting. The 

 last new one was made by Messrs. Walker Brothers 

 of Wigan, and has two cylinders, each 24 inches 

 diameter by 4 feet 6 inches stroke, with 1 1 feet 

 drums. In the year 1898 a bed of quicksand 

 was tapped in the mine, which established a con- 

 nection between the sea and the underground 

 workings, a cavity being formed on the outer fore- 

 shore, and a heavy rush of tidal water into the 

 mine took place, passing many fathoms below the 

 foundations of the sea wall. This however was 

 promptly checked by filling up the cavity on the 

 shore with furze and clay, but not before the sea 

 wall showed signs of distress through deflection, 

 caused by the undercurrent of tidal water into the 

 mine. The clay embankment behind the wall 

 subsided about 5 feet, and this subsidence had the 

 effect of shutting off the connection with the sea, 

 and the influx of tidal water shortly after ceased. 

 Mr. Matthews, of Messrs. Coode, Son & Matthews, 

 having been called in, advised that the sea wall 

 would stand, provided it were not exposed to 

 heavy strokes from the sea, and he designed a 

 wave breaker of pell-mell blocks of concrete (20 

 tons each), which was placed in front of the 

 damaged wall, and which has effectively protected 

 it from sea action. He also not only levelled up 

 the subsided embankment, but added to it also 

 both in height and width, so as to give additional 

 weight, and thus aid in shutting off the leakage 

 into the mine. This accident had the effect of 

 hastening the negotiations for the erection of an 

 outer barrier, the necessity for which had already 

 become apparent through the discovery of the fact 

 that the ore body extended a long way seaward of 

 the existing sea wall. In view of previous ex- 

 perience, Mr. Matthews, in designing this new 

 and larger structure, which like its predecessor had 

 to be both water-tight and sea proof, provided for 

 a flexible bank instead of a rigid wall, so as to pro- 



vide for such contingencies hereafter as connection 

 between the outer foreshore and the mine, should 

 such again occur. 



OUTER BARRIER (figs. I and 3) 

 The following description of this work has 

 been written by Mr. H. Shelford Bidwell, 

 the resident engineer under Messrs. Coode, 

 Son & Matthews : 



The outer barrier consists of a bank of rubble 

 limestone, protected on the seaward side for the 

 greater portion of its length by an outer covering 

 of 25 ton concrete blocks deposited pell-mell, an 

 inner and smaller bank of slag, with a filling of 

 clay between these two banks. Where concrete 

 blocks are not used, the bank is protected by large 

 lumps of limestone weighing from 8 to 15 tons. 

 Under the centre of the clay bank, in order to 

 form a cut-off preventing percolation of water be- 

 neath the barrier, tongued and grooved sheet piling 

 is driven into the bottom, this being of pitch pine 

 varying in length from 1 8 to 27 feet, or of steel 

 32 to 35 feet long, according to the nature of the 

 foundation. Where the natural clay is near the 

 surface the piling is dispensed with, and a puddle 

 trench is substituted, the puddle being well keyed 

 into the natural clay. 



Over the piling or the puddle trench, as the 

 case may be, a puddle wall is constructed in the 

 heart of the clay bank to prevent percolation of 

 water through the barrier, being brought up to a 

 level of five feet above high water of ordinary 

 spring tides. The surface of the clay filling is to 

 be covered with a layer of slag, and provision is 

 made for a parapet of concrete blocks if found 

 necessary. There will be four sluice culverts 

 through the barrier, constructed of concrete-in- 

 mass, faced at the openings with granite masonry. 

 The total length of the barrier is 6,870 feet, or 

 rather more than a mile and a quarter. It has an 

 extreme height of 40 feet, and its greatest width 

 at the base is 210 feet. The area reclaimed by 

 this barrier will be 1 70 acres. The contract for 

 the work has been entrusted to Messrs. John Aird 

 & Co. of Westminster, who, as already stated, 

 were the contractors for the first sea wall. 



WHICHAM PARISH. The principal mining 

 operations carried on here were those of the 

 Whicham Mining Co., begun about the year 

 1877 and continued until the year 1895. 

 During this time about 300,000 tons of 

 haematite were raised. Owing however to 

 the ore deposit not being sufficiently large to 

 meet the heavy expenditure incurred by 

 pumping, etc., it was found impracticable to 

 carry on the mines profitably, and this ulti- 

 mately led to their abandonment. The returns 

 of ore from the Millom district during the last 

 three decades will be found in Table No. VI. 



ESKDALE DISTRICT 

 ST. BEES PARISH. Several veins of ore 

 have been worked at the head of Eskdale 



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