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A Cwmorthin Interlude 1925-1939 FROM RHIWBRYFDIR FAWR TO GLODDFA GANOL CHAPTER TWENTY EIGHT A CWMORTHIN INTERLUDE 1925 - 1939 © J.G.Isherwood , January 2008 Page 1 of 10 © J.G.Isherwood , January 2008 A Cwmorthin Interlude 1925-1939 Inspection and Consideration In early 1925, it was decided to “do something” about Cwmorthin. It will be remembered that the quarry had effectively been abandoned since the early years of the century and it was obvious that a thorough inspection would be necessary in order to determine what produce could be expected from the old workings. Percy Jones reported as follows in February 1925: “The manager and myself went over to Cwmorthin and made a careful inspection of the surface outcrop workings on floors 7 and 8 of this quarry and found on going underground into floor 7 the operations of the late company and of the workmen who were afterwards allowed to get what they could and to rob the upper parts of the walls has resulted in practically wrecking the inside and brought down a good deal of rock underground rendering it absolutely unsafe and unsafe to open any chambers on this floor. “ “On floor 8 we found the old level had been driven for about 60 yards in the middle of the vein, with no attempt at chambers as it is too near the surface for opening underground workings. Therefore it leaves us no alternative but to start by open untopping to get at the rock uncovered by that operation. After fully examining the adjacent locality we found the most convenient and cheap tipping ground is available by utilising the old collapsed Back Vein sink. The sides of which have largely collapsed and which can never again be worked and after it has been tipped across to carry on the tipping in a North westerly direction parallel with the Cwmorthin Lakeside where there is space to receive a very large quantity of debris with a high tip and a convenient direction. The convenience of this tip ground will greatly reduce the cost of untopping and the tips of both 7 and 8 floors can be carried on simultaneously and start within 200 yards of the actual untopping. “ “The manager and myself have carefully considered and agreed upon the most convenient points on floors 7 and 8 to start the untopping operations and as to the line of the proposed bon which must be cut for the untopping on floor 8 it will be for some time almost entirely in drift... solid rock on that floor until it has gone into the breast of the hill but on floor 7 the slate rock showing in the old quarry where that level commences to go underground suggesting that we may expect to have Old Vein rocks much more quickly and once they commence to produce blocks there should be a progressive but not large increase of output. “ “The first steps are to provide rubbish wagons and rails and to put into working order and condition the top incline from floor 8 to floor 6 and the long lower incline from floor 6 down to the mills floor. The drum of the floor 8 incline wants replacing altogether, that of the floor 6 incline is in fair condition and only needs clearing of rust and oiling and the roof of the drumhouse repaired. Both inclines require new rails, sleepers, ropes and rollers. “ The next necessity considered was the provision of mill facilities for sawing, splitting and dressing of the slate. Upper or Cross Mill The upper or cross mill has shafting and dressers though the sawing tables have been removed, but the water wheel and the siphon which supplies power to it are in position. It only requires the troughing and a cistern to feed the siphon and the roofs and walls repaired. the mill which holds ten tables could then be operated by water power from Cwmorthin Lake, as it was in former times. It is conveniently situated near the foot of the feeding incline from the working floors. Lower Mills. 1/4 mile lower down are the two adjoining blocks of the lower mills containing 10 in the upper and 11 in the lower parts together with a number of dressers. the shafting pulleys and underground water wheel of the driving gear are all in situ and this cheap power could be restored at a moderate expense, although the operation of these mills by water power from Cwmorthin lake is attended by some small amount of uncertainty in summer and long periods of drought. So the question of supplying more reliable and costly sources of power such as oil or gas driven engines is worthy of consideration, and I understand that the manager and the mechanical engineer have been instructed to prepare comparative estimates of costs to re-install the cross mill and the upper 10 tables of the lower mill and for operating or both of them by oil, gas, or water power. In addition to the preliminary work described above were the necessary working tramways, weight tables and sidings on floors 8 and 7 and the tramway connection between the incline bottom and the mills, it was also obviously necessary to repair the main tramroad and inclines from the Mills down to the Ffestiniog Railway. Percy Jones continued: “My present view is that a large output of slate from Cwmorthin is not to be expected at any time as I think the probable output from the concern at any future time is not likely to exceed 300 to 350 tons per month. At the same time it will be all Old Vein slate, with the smaller sizes predominating, although the outcrop indicates a moderate production of large sizes and in any event it can be cheaply developed as an open quarry for two and possibly three floors in depth as although the ground rises very rapidly towards the Oakeley Quarries I do not think that the vein will be found to improve in quality as it outcrops higher up the mountain. The proposed allocation of £5,000 to carry out these various works will go a long way to preparing for the initial production, but I anticipate it will be found necessary to expect 20% to 25% more before this quarry can be sufficiently reopened to produce from 250 to 300 tons per month. Its situation necessitates it being carried on as a separate concern but under the control of the Oakeley Quarry manager, in this connection it is fortunate that a convenient and safe footway through the new Page 2 of 10 © J.G.Isherwood , January 2008 A Cwmorthin Interlude 1925-1939 level to the old GlanyPwll Quarry can be cheaply made which will connect floor 11 of the Oakeley and floor 8 of the Cwmorthin in a fairly convenient manner with a minimum of bodily exertion." 30/3/1925 During February and March, both the Oakeley Manager, Robert Jones and the Chief Engineer, T.J. Williams, prepared estimates and reported back to the Board as a result of which Percy Jones was called in again: "In accordance with your request, I recently attended at Cwmorthin Quarry with the Manager and Mr.T.J. Williams the chief Quarry Mechanic and inspected the levels on floors 7 and 8 Cwmorthin so far as accessible, took aneroid readings along the outcrop between the Upper Quarry and Cwmorthin to the site of the intended untopping, went through the mills considered and discussed the estimates prepared by Mr. Robert Jones and Mr. T.J. Williams and beg to report as follows: QUARRY DEVELOPMENT: I was agreeably surprised to find that much good work had been done by the two men clearing the accumulated rubbish, preparing the site of the tramways and inclines down to the mills floor to receive the permanent way, it would be advisable in order to avoid confusion between the floor numbers at the Oakeley and Cwmorthin lies respectively to adhere to the Oakeley numbers when dealing with Cwmorthin, and I find on checking the altitudes, the top Cwmorthin Level, that from which the dam was removed and which we call for purposes of identification, "the old dammed level" is on the same horizon as the Oakeley floor 11, the floors therefore, of the proposed open quarry would be: Floor 10 - Cwmorthin equivalent floor 7 and the lower floor of the untopping. Floor 11 - Cwmorthin equivalent floor 8. Floor 12 - New floor Cwmorthin, 50 feet above floor 8. Floor 13 - New floor Cwmorthin, 50 feet above floor 12. The old dammed level goes in a diagonal direction N.E. for about 50 yards, and the breast has not yet struck the clay slant, although very near to it. It is in good Old Vein rock and I am fairly of opinion that the level should be driven on until it strikes the clay slant and then proceed under it. Before proceeding far the upper portion of the old chambers opened by the Cwmorthin company will probably be driven into and it should be a simple matter to re-roof, widen and work these chambers as the depth of cover increases as progress is made going east. Ultimately this level may tap the old Upper Quarry chamber 27 and in any case should be productive of a regular supply of slate blocks. I have no doubt, nor has the Manager that good Old Vein slate can be quickly won by this method and so anticipate the production to be got by the old and slow processes of untopping. The prolongation of this level and re-opening the old Cwmorthin chambers would in no way hamper the ordinary process of untopping.