THE PARYS AND MONA COPPER MINES
Paper delivered to the Annual General Meeting of the Anglesey Antiquarian Society, 1960
by Edwin Cockshutt
It is not necessary to say anything to the members of this Society about the location of Parys Mountain; nor, indeed, about the early history of the famous mines which once controlled the world price of copper, and for a period kept nearly all the mines in Cornwall in a state of idleness. It is said, too, that Nelson's victories were founded on Parys and Mona copper, for his men-of-war were all copper-bottomed from these mines.
So much has been written in the past that another paper on the subject might well seem superfluous, were it not for the fact that time and weather are rapidly obliterating all traces on the mountain of man's efforts to win, raise, and carry away the precious metals so liberally supplied by nature in this area. It seemed to me to be worth while to place on record, before it is too late, the nature and use of some of the many buildings whose shells and foundations cover the mountain, and to make use of records now available to illustrate the method of working the mines, and to shed some light on the problems of management and labour in the 18th and 19th centuries.
Between 1955 and 1957, too, a thorough investigation of these mines was carried out by certain mining interests, some eighteen months being spent by engineers and geologists both above and below ground. During this period, an extensive laboratory and crushing plant were set up in the village of Pentre Felin at the north-eastern foot of the mountain, and thousands of samples were taken, analysed, and recorded. Much capital was sunk in this investigation, and the quality of the engineering work carried out, and the materials used, were the best ever seen on the mountain during the present century. Some of the results of all this work were made available in a paper read by the Engineer-in-Charge, Mr. W. Manning, A.R.S.M., B.Sc., A.M.I.M.M., at a Symposium on British Mining held in London on the 24th September, 1958, under the auspices of the Institution of Mining and Metallurgy; and I am greatly indebted to Mr. Manning for permission to make use of his paper, and especially for the loan of his 25 inches to the mile geological map of the surface of the mineralised area, and also of the corresponding sections. It is a pleasure to testify to the accuracy and value of this map. after a careful field check.
In order to fully understand the problems which faced the miners of old, it is now necessary to say something about the geology of the area.
A visitor to the mountain approaching from the east would first come to a vast pit or opencast working. This is the Mona Mine Opencast, and, as he progressed westward, the visitor would soon see a vaster, though somewhat shallower pit, known as the Parys Mine Opencast. It should be borne in mind throughout all that follows, that the Mona Mine occupies the eastern half of the mountain and the Parys Mine the western half.
These two mines occupy a mineralised belt over 5000 feet long, and more than 1200 feet wide; its major axis on the " strike " of the lodes, running north-east. The area is bounded on the north by the Llannerchymedd-Amlwch road; on the west, by a line drawn due south through the " Western " and " Hughes Incline " shafts; on the south, roughly by a line drawn through the farm buildings of " Plas Newydd", "Trysglwyn Isaf ", and the centre of Penysarn village; and on the east, by a north-south line passing through the " Henwaith " shaft.
Some 400 yards further to the west, we come to another and smaller mineralised zone constituting a separate mine known as " Morfa Du ". This is situate almost wholly to the west side of the Llannerchymedd-Amlwch road, its northern boundary being the huge quartzite boss near to the road, so polished by glacial action that It shines in the sunlight; its western, the bottom of the hill upon which the boss stands; its southern, the small chapel on the West side of the road, and its eastern, the " Shaft Wen ", not far from Pen y Nant farm.
The whole of the above was mapped geologically by Dr. E. Greenly about the year 1910, to a scale of 25 inches to one mile and again in 1955-1957, by Mr. Manning, to the same scale.
To the north and east of the mineralised zone, the Amlwch and New Harbour group beds of the Mona Complex have been carried over the Ordovician Shales of the northern slopes of Parys mountain, by the enormous Carmel Head Thrust which extends from Carmel Head almost semi-clrcularly across the northern coast of Anglesey and its hinterland, returning to the sea again near Point Lynas. These beds appear as finely crumpled, chloritic green schists. A similar. shallower thrust from the cast, known as the Corwas Thrust, cuts off the cupriferous felsite at Hen Waith. On the southern boundary, around Trysglwyn Isaf and Penysarn, micaceous, quartzitic, and granitoid gneisses all appear.
The northern side of the mountain consists entirely of Ordovician shales, light green, light grey, and also black and sooty in appearance and intersected by porphyritic dyke and quartzite in many places. At the top of the mountain, near to the windmill, the hard, siliceous, Carreg y Doll lode outcrops, striking east and west, and north-east, north-west, for over half a mile.
In the core of the mountain are the Silurian rocks, and to the south of them again, black and fissile shales, often showing cubic crystals of pyrite. Within these shales, on the hanging wall, or north side, is a black, cherty rock, containing pyrite in minute cubic crystals, and veinlets of zinc blende and of pyrite, with bunches of chalcopyrite. This is the noted " Bluestone Ground ", containing lenses of bluestone. Some of these must have been at least 700 feet long, and 180 feet wide. Below the black shales are light grey coloured shales and light grey mudstones. To the south of the mountain, black shales again appear, also Silurian, but quite different to the northern series, being far more gritty.
The core of Silurian shales is bounded on the north, west, and south sides by two limbs of felsite, so disposed as to make up the body and prongs of a huge tuning fork (Fig. 1). This rock is highly silicified, especially in the northern limb of the tuning fork, and contains nearly everywhere well formed, pin-head size, cubes of pyrite. This northern limb is dark grey in colour, and contains up to 19% sulphur. Within it lie the majority of the old workings. Nothing but the result of unsuccessful trials is to be seen in the southern prong of the tuning fork. Its felsite is not cupriferous.
Within, or traversing the felsite, lies a dark green rock weathering to a typical brown colour; this contains cubic pyrite crystals up to inch square, and is often traversed by fine hair veins of chalcopyrite. The " Golden Venture " shaft is sunk in this rock, and the Golden Venture lode is entirely within it. In some areas, a lighter coloured green rock appears, possibly a chloritised felsite.
FIG. 2.-Cross Sections, Parys and Mona Mines
On turning to the sections through the mountain, (Fig. 2.), it will be seen that all lodes, and also the bluestone ground, dip steeply to the north; and that all the old workings lie to this side. Both the northern felsite and the bluestone ground show intense silicification. Following upon the silicification, quartz was injected into the Silurian shales and felsite along irregular fissures, the largest amount being on the contact of the felsite (and green dyke) and the Ordovician shales, giving rise to the Carreg y Doll zone, i.e. the whole system of quartz ore bodies north of the felsite. Where quartz disappears, there is silicification of the shales. Probably following upon the phenomena described above, pyrite was deposited in all the rocks except the Ordovician shales and the Mona Complex. Subsequently, a later generation of pyrite is observed following the quartz stockwork, or building up its own system of pyrite veins (up to 4 inches in width), in both the bluestone ground and the felsite. The Carreg y Doll lode is highly pyritic, the pyrite being of the second generation already referred to. Chalcopyritization followed, being deposited in the same stockwork as the pyrite. (Pyrite is Disulphide of Iron, Fe S,, and Chalcopyrite is Sulphide of Copper and Iron, Cu, S, Fe, S,.) Next followed lead-zinc mineralisation, chiefly in the bluestone ground where small lenses can be seen. The bluestone is a fine grained, dark blue to black ore, containing when pure some 30 % Zn, 1 0 % Pb, 1 % Cu, and some pyrite.
Examination shows the factors determining ore deposition in the mineralised zone to be shears along or near contacts of shales and felsite. The shear fissures have been opened up by gradually increasing silicification and quartz injection, or brecciation followed along the old lines of weakness, the mineralising solutions rising along these new fissures. There is no reason to expect these shear zones not to continue in depth.
Dr. Greenly showed that the mountain felsite would originally have been a sill, nearly conformable to the shales, and infolded with them; while the Silurian rocks would be of limited depth, and so would be the felsite also, and at a greater depth the Ordovician would he found, through folding or thrusting, or both. Mr. Manning, however, holds that the evidence is also consistent with the felsite being a forked dyke of transgressive character, in which case mineralisation may continue in depth in the stem of the tuning fork. In his opinion, there is a distinct possibility that the mountain has roots, and has not been carried forward in a southerly direction along the " Rhwnc Thrust Plane ". as Dr. Greenly suggested. The fact that these roots exist and whether they are mineralised or not could be proved by diamond drilling below the level of the old workings, at an angle of some 60' to the horizontal. Drilling sites should be selected along the northern face of the mountain, and in the fields to the north of the Llannerchymedd-Amlwch highway. Drilling at a steep angle should also be undertaken to the east of Henwaith, to prove the mine below the Corwas Thrust Plane. This appears to be a better prospect of proof in depth than that afforded by unwatering the mine, which would cost about �6,000, and occupy some 50 days, using 600 gallons per minute pumps, working against a head of 600 feet. Diamond drilling would be somewhat more expensive than this, and at least �60,000 of risk capital should be available.
THE WORKING OF THE MINE.
Compared with modern practice, the Parys and Mona Mines would certainly be termed " shallow mines ", the greatest depth obtained being only 900 feet at the bottom of the " Gwens " incline shaft. Modem mines on the Rand operate at ten times this depth. Ventilation was induced naturally, which meant a large number of shafts, comparatively closely spaced. The major shafts in the Parys Mine are spaced up to 500 feet apart, as compared with 300 feet in the Mona Mine. Shaft sinking followed Cornish practice closely. Indeed, the mine captains were often Cornishmen, and as they gave their own names to the shafts they sunk, we have on the mountain, " Tiddy's ", " Treweek's ", " Lemin's ", and " Beer's ", all in the Mona Mine. There was no standard size for the shafts, The mouth of the shaft would be timbered as necessary, to suit the nature of the overburden. Mr. Manning accounts for over 80 shafts on the mountain, but including the large number of trial shafts he was personally responsible for in the bluestone ground, I have counted 102 and am still adding abandoned trial workings stumbled upon from time to time.
Associated with the shafts were " footways ", whence, by descending some stone steps hewn in the rock, the first level could be reached; further descent being effected by means of ladders in the " Whinses " or short shafts connecting the levels. Two principal footways are usable today, the Parys Footway giving access to the ten fathom level, and from which the whole of both Parys and Mona Mines above water level can now be explored; and the Mona Footway, or, as it is often called from the shaft adjacent to it, the Henry Footway. This is now a bad route, being exceedingly dirty, and somewhat terrifying too, as one passes a great rush of water, hidden away in the darkness somewhere. Indeed, it is only fair to warn anyone who may wish to go underground, that they will never again wear the clothes in which they visit the old workings.
A glance at the longitudinal sections (Fig. 3.) will show that the major (engine) shafts give rise to a number of horizontal galleries or " drives " as they are termed. These have an average size of 6 feet by 5 feet, and follow in the course of the lode, along the strike. Galleries driven through the country rock roughly at right angles to the "drives " and often connecting the various lodes, are known as " crosscuts ". " Drives " connect with the one above by mean of short shafts known as " raises " if driven upwards from below, and as " whinses " if driven downwards into the next drive below. Thus, the whole lode is sub-divided along its strike by means of " drives ", " whinses " and " raises ", into rectangular compartments in which the miners hewed out huge chambers in the lode, known as " stopes ". These are indicated on the section (Fig. 3) by the dark patches. Eventually, the drives, whinses and raises completely disappear, as stopes one above the other merge into huge caverns. One such, in the Mona Mine known as the Cairns Stope, is over 400 feet in depth. This is reached from the Cairns Shaft, and was known to the old men as the Stope Mawr, or Hugh Hughes Penygraigwens work. In modern practice, haulage ways would not be driven in the lode, but in the country rock below it, the stopes being connected with them by means of short raises.
Drainage of mines, often a vital consideration, is effected by means of a special drive, usually the first level, known as an " adit " and driven through to surface somewhere out on the hillside. The adit serves to remove surface drainage, and to provide a means for pumping out the mine as necessary. Fortunately, neither the Parys nor the Mona Mine make much natural water, not more than about 75 gallons a minute all told, an amount easily within the capacity of the wooden pumps and beam engines used by the old men. Parts in contact with copper water had to be of wood, as no metal then known could withstand the corrosive action of water impregnated with copper salts. Incidentally, such water from the mountain is eagerly sought after by local farmers, in order to treat foot-rot in sheep.
In the Mona Mine, the mineralised areas are all connected by a common adit, draining down to a main adit surfacing in the bluestone ground, and feeding the precipitation pits adjacent to Hen Waith. Thus a further means of access to the mine, though a dirty one, is afforded, through which all shafts can he reached. Part of the Mona Mine lies within the Great Opencast to the west, and the advantage of a joint drainage level was clearly seen by both companies.
This crosscut was driven from the Boundary Shaft footway in the opencast, 600 feet north north-east, and then directly north, at the 45 fathom level, to break surface near Dyffryn Adda, Pentre Felin. Should the mines ever be unwatered, this could be very conveniently done from the Dyers Shaft, which is not far from this Joint Level.
At a point on the boundary between the two mines, where the Joint level changes direction opposite the " Shaft Fawr " in the Parys Mine, was driven in 1904 the last great underground work, namely, the Intermediate Level in the Mona Mine. This was separated from the Joint Level by means of a rockwall dam, fitted with drainage plugs, and with space at the top for a man to crawl over from one mine to the other. This dam has now been destroyed.
The Intermediate Level leads directly to the Cairns Stope, the descent into which is highly dangerous.
Turning now from the underground workings, we have to consider the method of working the two huge excavations known as the " Opencasts ", Mona and Parys, respectively. A glance at the cross-sections of the mountain (Fig. 2.) will indicate what was accomplished by excavation from the surface, largely in the bluestone ground. In 1887, Mr. R. Hunt published his famous treatise an British Mining. This work contains two fine woodcuts showing the method of working the Mona Opencast. When excavation was comparatively shallow, vertical-spindle, man-operated, winding drums known as " whimsies " were erected close to the edge of the overburden, by means of which a bucket known as a " Kibble " was lowered to the miner below; who excavated for himself, first a foothold, and finally a cavern in the bluestone ground, winding proceeding while he was excavating. As the opencast deepened, it was found necessary to change the type of whimsie, so as to avoid the bucket striking the rock face, and discharging its contents on to the men working below. Whimsies now had a horizontal spindle protecting well over the rock face, but mounted as before on the edge of the rock.
Normally, when a mining lease is about to expire, and will not be renewed, the lessees cease to develop the mine further, and concentrate on raising as much ore as possible. So it happened on Parys Mountain, but the lessees cut away more of the supporting rock than was safe, and the whole of the overburden collapsed into
the workings one fine day. This overburden was found to be extremely rich in lead, yielding 600 to 1,000 pounds per ton.
The Reverend W. Bingley writing of his tour in Anglesey in 1798, says of this opencast : " On the morning of my arrival at Amlwch, I walked to the top of Parys Mountain. Having ascended to the top, 1 found myself standing on the verge of a vast and tremendous chasm. I stepped on one of the stages suspended over the edge of the steep, and the prospect was dreadful. The number of caverns at different heights along the sides, the broken and irregular masses of rock which everywhere presented themselves ; the multitudes of men at work in different parts, and apparently in the most perilous situations ; the motions of the whimsies, and the raising and lowering of the buckets to draw out the ore and the rubbish ; the noise of picking the ore from the rock, and of hammering the wadding when it was about to be blasted with at intervals, the roar of the blasts in distant parts of the mine altogether excited the most sublime ideas, intermixed, however, with sensations of terror. I left this situation and followed the road that leads into the mine ; and the moment I entered, my astonishment was again excited. The shagged arches and overhanging rocks which seemed to threaten annihilation to anyone daring enough to approach them, fixed me almost motionless to the spot. The roofs of the work having in many cases fallen in, have left some of the rudest scenes that imagination can paint ; these, with the sulphureous fumes from the kilns in which the ore is roasted, rendered it to me, a perfect counterpart to Virgil's entrance into Tartarus . . . To look up from hence, and to observe the people on the stages a hundred and fifty feet above one's head ; to see the immense number of ropes and buckets, most of them in motion, and to reflect that a single stone casually thrown from above, or falling from a bucket, might in a moment destroy a fellow creature ; a man must have a strong mind not to be impressed with many unpleasant sensations, A few days before I was last here, a bucket caught against the point of a rock, emptied its contents on to the head of one of the miners, and killed him on the spot.
The sides of this dreadful hollow are mostly perpendicular. Along the edges, and in general slung by ropes over the precipices, are the stages, with windlasses, or whimsies as they are here termed, from which the buckets are lowered ; and from which, those men descend who work upon the sides. Here, suspended in mid air,
they pick with their iron instrument a small place for a footing, cut out the ore in vast masses, and tumble it with a thundering crash to the bottom. In these seemingly precarious situations, they make caverns in which they work a certain time, until the rope is again lowered to take them up."
Men actually employed in ore-getting were known as " Tributers ", while those solely engaged in development work such as sinking shafts and extending the drives, were known as "Tutworkers ". For the origin of these terms, one must look to the Stannaries Law of Cornwall. The tributer originally received a portion of the ore got out, as his " tribute ", while the tutworker worked chiefly in the country rock, and was paid by the fathom.
Bingley again gives a lively description of the method of oregetting: "A hole is bored in the rock, of about the diameter of a wide gun barrel, and of depth in proportion to the quantity of matter to be thrown up. At the bottom is lodged the gunpowder, and the man, then taking a thin iron rod tapering to a point and about two feet in length, places it perpendicularly in the middle of the hole, and fills it up on all sides with stones, clay, etc. ; ramming these hard down by means of an iron projecting at the bottom, with a nick in it, that it may pass freely round the rod. When this is prepared, the rod is taken out and a straw filled with gunpowder is substituted. A match is then put to it that will burn so long before it communicates fire to the powder as to allow all the workmen within reach to escape into different retreats from the danger attendant on the explosion. Several blasts are generally ready at the same time, and notice is given to the workmen to run to shelter by a cry in Welsh of " fire ". Whilst I was in the mine, the cry was several times given, and I with the rest crept into shelter. In one instance, six or seven blasts went off in different parts successively one of which was within 30 yards of my station, and the splinters of the rock dashed furiously past me. The process of blasting is frequently attended with danger, from the carelessness with which the men retire to their hiding places : and it sometimes happens that in ramming down the wadding, the iron strikes against the stone, and fires the gunpowder. This generally proves fatal to the man employed. During the short time I remained here, I observed upwards of forty men in different places occupied in this work ; and I felt somewhat uncomfortable under the idea that in such a number, someone might be careless enough to have his gunpowder take fire before he was aware of it."
Modern visitors to the underground workings may he somewhat mystified to see so much straw lying about. In addition to holding the blasting charge, this straw was used to form a cap for the drill, to reduce the splash of water from the hole when drilling. This was known as a " Cap Ebyll ", or drill cap. Straw was also used to make a " Hwyaden gwellt ", or straw duck, for sitting on, or placing under the knee when drilling. The first drill used was always broader than the others, and was known as a " pitcher ".
We are now in a position to make a tour of the mountain, and to pause here and there to reconstruct something significant from the low walls and foundations to be seen all around us. These are the sole indication to-day of a copper industry which once dominated Europe in both war and peace, but has now completely vanished from Great Britain.
Let us commence in the North East corner of the Mona Mine, where the old road to the mines runs in a straight line towards Amlwch. Right before us lies a farm house, "'Taldyffryn ", and on the corner of the lane in front of the house is a shaft still containing pipework and foundations of the pumps which supplied fresh water to the boilers of the steam-pumping engines on the mountain. To the east of Taldyffryn is a freshwater lake known as Llyn Coch, of ample capacity for boiler feeding. Water from this lake was fed to a water wheel, a little way down the mine road. After operating this wheel, the water ran on to a shaft in which the plunger pumps were located. These pumps, operated by the water wheel, lifted the water up to a large reservoir behind the ivy-covered engine house known as the Pearl Engine, or more commonly today as " Engine Cerrig y Bleiddiau " the name of this locality. After feeding the boiler at the Pearl Shaft, the engine pumped more fresh water from the reservoir, right up to the top of the mountain to another boiler situated at the Cairns Shaft, a little to the west of the summit windmill. The total lift from the water wheel to the Cairns boiler would be about 200 feet. Proceeding up to the Pearl engine house, we notice that the boiler was located on the north side, and wonder how the pump rods from the great beam of the engine managed to reach out to the Pearl Shaft some yards to the south. The answer is to be found in an old photograph in Owen Griffith's book, " Mynydd Parys ". Here are plainly to be seen two beams, the upper one working the lower one, which has a large balance weight at its southern end. The boiler feed water reservoir is also clearly to he seen. It is well worth recording too, that there is in the possession of the Misses Thomas, at Taldyffryn, a painting showing the pumps by the water wheel as erected complete with the beam-mounted balance weights which ensured the smooth action of the pumps.
The underground workings at the Pearl Shaft are not very extensive, being no more than 600 feet along the strike of the lode, though, at the lowest point, they reach 100 fathoms. The section Fig. 4 shows a vertical shaft which does not reach the lode until sunk to 90 fathoms. The ideal would have been to have sunk a shaft intersecting the lode at half its depth and then to drive both north and south at different levels. This ensures the greatest economy in working, and it is clear that had surface indications held in depth, this ideal would have been realised. As it turned out, however, the 20 fathom level drive went south for 180 feet before reaching copper, instead of the ideal 120 feet. The lode intersected is the Carreg y Doll, the hardest to work on the mountain, and of very low yield. No doubt this accounts for the small extent of the workings.
Proceeding up the hill towards the summit, we leave on our left the Cerrig y Bleiddiau group of shafts, with the Stephens group on our right. Up above us, on top of the bank, is the Marquis Shaft of the Mona Mine. This is an incline shaft, following the lode down to the 90 fathom level of the Pearl Shaft, and according to an old minute book recently unearthed by Mr. Sidney Taylor of John Taylor & Sons, one of the early lessees of this mine, a rich bed of bluestone lies between 50 and 90 fathoms. Unwatering would be necessary in order to prove this. But the fact remains that cast of the Dyers Shaft in the Parys Mine, and Tiddy Newydd Shaft in the Mona Mine, near to where we now are, and the last shaft to he sunk in the Mona Mine, lies a large patch of unworked and unexplored ground, in which, according to Mr. Manning, the North Discovery Lode, the richest on the mountain, could re-make, both in strike and in depth.
We now come to a small triangular patch of ground on which stands a modern explosives magazine used in the recent prospect of 1955-1957. Away to our right, hidden amongst the rubbish dumps, and indeed, now hardly discernable, lies the Lemln Shaft. It was here that a large quantity of dynamite which had deteriorated in this magazine, was lowered some way into the shaft, and then detonated. The resulting bang is still spoken of with awe in the village .of Penysarn.
Now, on our left, and almost under our feet, is the Golden Venture Shaft, and here we turn sharp right, around the shoulder of the prominent rock known as " Carreg y Doll ", the rock of the toll-taking, an outcrop of. the lode of that name. This lode forms the backbone of the mountain, and is the only one which is continuous through both mines. Two shafts are associated with it, an old working called Francis, on its southern side, and an important engine shaft situated at its western end, on the adit crosscut linking the Charlotte, Carreg y Doll, and Clay Shaft lodes, and known as the Carreg y Doll Engine Shaft.
In connection with this engine, there is a story too good to be omitted. In 1860, there began a great strike in the mines during which the strikers were accustomed to assemble on the Mountain in the afternoons in order to hold a Prayer Meeting in the open air. Pumping operations were continued by the management throughout the strike as an essential measure, and among the engines so working was that of Carreg y Doll. One afternoon while the usual Prayer Meeting was being held, the flywheel and connected gear trains on this engine burst, causing a general wreckage in the engine house. A messenger at once rushed off to the Prayer Meeting, and requested the participants to cease, " before every wheel in the mines is broken ". In this connection there is a significant statement in the Plas Newydd Papers under May 6th, 1865 : "Steam engine at Carreg y Doll patched up, and supplied with new boiler, but larger modern unit required ".
Across the way, over the dump on the right, is a flat level space known as the Charlotte Yard from its proximity to the Charlotte Shaft slightly to the west. This was the workplace of the famous " Copper Ladies " of Parys Mountain, in the Mona Mine. Here, wearing an iron gauntlet, they dressed the ore from the Charlotte, Cairns, and Lemins Shafts nearby ; the huge dump immediately to the east bears eloquent testimony to both the magnitude and efficiency of their labours. In a long low shed sat the " Copper Ladies ", with a hundredweight anvil by their knees, known as a ' knockstone ', and wearing on their left hand a thick glove, with the fingers encircled by iron rings formed from short tubes. With this glove, they dressed the ore on the knockstone from the heap set by their side, using a short narrow hammer in their right hand.
A hard worker would receive the sum of tenpence a day for twelve hours of labour. Before leaving the Charlotte Shaft, I would say that I have been solemnly assured that there is a " bwgan " (ghost) in the adit driven to the north. I deem it worth recording such locations on the plans, for no doubt, the " ghost " was raised to keep people away from a pocket of good ore, or a small dump of such hidden away in order to enrich samples. Such locations might be worth detailed investigation when convenient.
From the Charlotte Shaft, it is only a short step to the south~ west to the windmill. This, with its five sails, was built in 1878, and was connected by means of long wooden rods to the crank of the Cairns Shaft engine some 200 feet away. When the wind was strong enough, the end of the connecting rod was placed on a crankpin, and the wind thus assisted the power of steam, effecting a large saving of coal ; for there are not many windless days on the summit of Parys Mountain. For many years, the stone entablature of the Cairns engine was a prominent feature of the summit, but now, only a heap of rubble remains. The pump rods in the Cairns Shaft, with their eye-llnks for attachment to the engine, are still to be seen. Close to the windmill on the south-west, is another shaft known " Sidney's ". This is sunk in an unproductive part of the Carreg y Doll lode, and the Plas Newydd Papers contain a complete account of its sinking, with costs and labour figures, giving high hopes of success at the commencement, and then saying how the Agent was tempted to " throw the kibble to the bottom of the shaft " i.e., to cut the rope that held the bucket, and so abandon the work.
Descending from the summit, we pass by the Sanderson Shaft with its circular track for the man or pony that operated the whimsey, then, the Drift Mawr Shaft above the Mona Opencast, and turn left on to the road between the two opencasts. A shallow depression as we turn the corner marks the site of the " Road Shaft ", and if we proceed to the edge of the Mona Opencast to the cast, we shall probably scare into flight one or more of the ravens that nest on the fissured face of the northern side. The size, flight and characteristic croak of these birds easily distinguish them from other members of the crow family. Again, if at the risk of your neck you climb about the adjacent fissures, you will be amazed at the enormous size of the spiders, whose webs span each fissure time and again. But this ground is really dangerous, as is also the floor of the cast pit, where the underground workings are so close to the surface that collapse might occur at any time.
Turning for a moment to consider the once enormous " Bell Rock ", whose fast weathering felsite is rapidly crumbling away, we pass by a shaft known as " Pen y Bone ", leading to an enormous cave, approachable at some risk, from the side of the opencast. This is known as " Gwaith Robin Ellis ", and good samples of pyritic rock and of verdigris can he obtained within it. Miners would call it a " heavy hanging ", for the roof threatens to come down on those who enter it.
Away to the right, we pass by the ruins of a smithy, the resort of miners whose tools needed attention. Many the Prayer Meetings held therein, and mighty the discussions based on the heavy ammunition of contemporary theologians.
Soon, we find ourselves heading for the " Mona Yard," the headquarters of the Mona Mine. Here, within the enclosing walls, were the offices of the mine, stores of all kinds, the mortuary, and the bell house, together with the workshops, stables, assay office and cart shed. Between the sampling house and the assay office stood an enormous pulpit, with a sad history. At the end of the eighteenth century, the mine authorities decided to demolish a chapel in the village of Rhosybol to the west. Most unwillingly the work went forward, and when the materials were put up for auction, there was not a single bidder. So, the whole of the timberwork was put into the yard for use in the mine. But many of the members of the old chapel of Lletroed worked for the Mona Company, and though the timber was there freely for their use, not one scrap of it ever went below ground, but it all lay in the yard until it had rotted away. All, that is, except for the pulpit, which was put to a use never contemplated by its builder. Once a month the Mine Captain and the Superintendent entered the pulpit carrying two large volumes and a box of small stones. In one book was recorded the bargains made with the Tributers, those who actually got out the ore at so much a ton; and in the other, those made with the Tutworkers for mine development, at so much a fathom. On conclusion of a bargain, a stone was flipped from the box, over the beads of the assembled workmen, by the Mine Captain, to denote the fact. Bargains have been let for more than �3 per ton, and for as little as a halfpenny a ton ; in the latter case to a syndicate of ten or twelve men.
The Plas Newydd Papers tell us that during the period 1817 to 1831, tributers underground were paid at so many shillings per pennyweight assay value, per ton of dressed ore. The commonest rate was 32/- on bargains described as poor, 28/-, on a very promising bargain. 24/- on a good course of ore, 21/-, when there was a large lode, and 16/- on a very good course of ore of good produce. Bargains on the waste heaps were all set at 24/-. Tutwork bargains were set at rates of from �4 to �8-10-0., per fathom. But on " Pay Saturday " the miner found set against his earnings for the month the cost of candles, powder, fuse, steel drills, hammers, pickaxes, spades, drawing the ore to the surface, sharpening and setting tools etc. All expendable stores had to he purchased from the company. Nevertheless, if after all deductions a balance remained to the credit of the workman, it was of course paid. But the next time that particular bargain was let, the price would be cut ; with the result that the bargain-taker would be in debt to the company at the end of the month, receive nothing for all his labour, and thus be tied to the mine until he could pay off the debt he owed.
To the credit of the company, it can he said that later on they sternly opposed this reprehensible system, as the following quotation from one of the Plas Newydd Papers dated 1862 shows : " Refers also to accounts for November showing debts incurred by tributers amount to the large sum of �69-0-8 " This is returning to the vicious system of your predecessors and is evidently due to your having overvalued the men's ore for subsists, - no subsists to be paid unless earned." Again, " complains of serious increase in the men's debts, on the month's accounts, which should be put a stop to for the future ". Also, in 1863, a notice draws attention to Trewren's practice of ' cooking ' the tutworkers' accounts, by charging ' stem money , - require him in future "to specify the work performed."
On the other hand, there appeared to be a completely " closed shop " system in operation amongst the workmen, most detrimental to natural progress ; for none other than Welshmen were allowed to remain in employment, the job being made too hot for them.
Writing to his Board in 1862, the Agent says: " The returns could be considerably and permanently increased by the application of skilled labour and greater industry and enterprise on the part of the native workmen: and although I am not at present prepared to advise the adoption of any active measures for putting down the existing monopoly of labour, so long established by the native labourers; I nevertheless consider it to be my duty on this occasion, to bring the subject under the notice of the Trustees for the purpose of making them fully aware of its injurious consequences to the miners themselves, as well as to their employers." Again, in 1864: " The evil in question is one of long standing ... in existence more or less since the commencement of the mines; and the Welshmen have been so uniformly successful in maintaining their monopoly, to the almost total exclusion of strangers from the mines, and moreover, have been, and still are, so strongly supported by the public feeling of the locality in their favour, that any attempt to eradicate or even to lessen it to any considerable extent, must necessarily be a work of time and difficulty . . . utmost circumspection and prudence required ... full and cordial concurrence of the managers and agents of the respective mines essential . . . avoid offending even the prejudices of the native population .... It Is highly desirable that the native miners should be stimulated by the example of experienced and skilful workmen from other mining districts, accustomed to the exploration of irregular veins and small deposits of ore ; on the principle of their remuneration being contingent on the produce of their labour : and for that purpose, it is essential that such men coming voluntarily to the mines to seek employment, should be placed on the same footing as the Welsh miners, and be permitted to enter into competition with them on equal terms for the work and also that they should be afforded efficient protection by the mining and local authorities against the absurd hostility of the native workmen." And again, " It is essential that the authorities of the two mines should act cordially in concert " ; but a covering note say " He was not very sanguine in his expectations of assistance from John Taylors, because Parys Mine is not so dependent on the Tribute System as is Mona." Always, Mona Mine lagged behind Parys in efficiency of administration and operation, and undoubtedly, herein lies one of the root causes for such a lag.
'We must now leave the Mona Yard and descend into the great opencast by the road once carefully graded to suit the traffic of horse-drawn vehicles. We pass on our descent the blocked mouth of the Dyffryn Coch Adit, another main drainage adit, discharging into the ochre pits on the south side of the mountain, not far from Trysglwyn Isaf. The huge rock in the centre of the opencast is of silicified felsite, and at the contact of the felsite with the bluestone ground to its south, traces of lead and zinc are to be found. Crossing by the old foundations at the east end of the rock where once stood the headgear and engine for the Marquis Shaft in the Parys Mine, we take a quick glimpse at the footway of the Boundary Shaft to our left and look up at the sheer face of the Great Crosscourse. This is a cupriferous rock which cut through the opencast and through which runs the boundary between the two mines. A steep climb brings us out to the level of the mouth of the Colonel's Shaft, now blocked by a heavy fall of rock, and soon we are at the top of the cliff again, close to the Parys Yard.
This yard, though much smaller than that of the Mona Mine, served the same purposes ; and is noteworthy for an incident which took place there once, when the mining lease was due to fall in. On a " Pay Saturday " word went round that the officials of the mine were not going to meet their obligations fully, so all the miners assembled in front of the office to obtain from the management a clear understanding on the matter. Due to the determination of the lease, a few of the lessees were present in person, along with the mine captain and other officials ; and the men were given to understand that they would not be paid in full. On failing to convince the lessees of the unrighteousness of this decision, the men determined to lay siege to the office and hold all therein prisoners, until they were paid the uttermost farthing. The men pressed menacingly against the structure of the office, but the lessees remained obdurate, though seeking every possible means of escape from the premises. But it was made perfectly clear to them that there was no hope of release until all had been paid in full. One of the lessees saw the futility of resistance to the men's lawful demands, and made his views known to his fellows, with the result that he was released from his imprisonment, jumped on his horse, and escaped. Throughout the afternoon the lessees remained obstinate, but finally had to comply with the men's requests and meet their just obligations, departing much lighter in pocket than they had originally intended.
One of them jumped on horseback and rushed out of the yard, just as the wind slammed the two wings of the double gates together. There he remained, struggling as in a vice, until he was released from this undignified position by the workmen, who had far more thought for the injured animal than for him.
We now return, via the road around the west end of the opencast passing first the Dinorben Shaft, high above the Parys Yard, and across the abyss ; the South Engine, or Water Whimsey Shaft, perilous of approach. Before long, we are back once more by the Mona Opencast, or East Pit, and after passing the ruins of a circular structure, once a powder magazine, turn north along a narrow track, over the Black Rock and Clay Shaft lodes, passing the two shafts so named. This area is known as " Hillside ", and soon we are amidst the mixed green dyke and felsite, around the Calciner Engine House and adjacent shaft. The Calciner Engine was an important one, for not only did it operate the Calciner shaft, but also pulley haulage gear for ore from the Black Rock, Tiddy Newydd, and Job shafts ; and also bored out the wooden pipes and pump barrels used in the mine. Pausing here to look around, we notice the remains of a chimney above the precipitation pits in the bottom, and see what appears to be a trackway running straight from the engine house to the chimney, and thence on, in a straight line, across the southern felsite to the embankment dividing the two huge pools to the south of the mountain. Close to the embankment lie the ruins of an engine house (engine Ty Main), and the adjacent driver's cottage known as Fron Heulog. Here stood a suction gas plant which pumped water from the lakes via a pipeline along the track we have just looked at. This pipeline passed right through the structure of the Calciner engine house, and thence straight on to the dumps near to the Cairns Shaft, whence it sparged its contents over a wide area. This water, soaking through the dumps, became heavily concentrated with copper salts, and perceptibly enriched the standing water in the mine. Each spring, this water is drawn off through a sluice valve in the Gardd Daniel Shaft, down to Dyffryn Adda, where, both copper precipitate and yellow ochre are obtained by the following process :
Old iron is thrown into shallow pits, precipitating the copper, which when the water is drained off, is scraped together in the form of powder, dried-off in a furnace, and bagged ready for the Smelter, or for use in the manufacture of paint. The reaction is: CUSO4 + Fe = Cu + FeSO4 the iron going into solution.
If the ferrous sulphate is further oxidised by pumping up to an artificial waterfall by Llyn Llaethdy, in which pool it remains for sometime, the solution process can he repeated by reducing the ferric sulphate with scrap iron once more.
Onwards from the Calciner we are now right in the bluestone ground, and the surface below is scarred with many shafts. Further on still, adjacent to the mouth of the Mona Main Adit, are many trial shafts, the remains of the 1955-1957 investigation ; and the diligent searcher amongst the shale from their dumps may recover some fossil graptolites. Due to the silicification, however, these are difficult to preserve, the shale soon turning to a dirty grey and crumbling away. It is a good plan therefore to carry a tube of cellulose acetate adhesive on these expeditions, and to coat the graptolite thinly immediately on discovery . This will preserve it indefinitely.
Descending towards Hen Waith, we can see close to some ruined stone steps down to the now dry precipitation pits, spoil from a trial level driven in 1956, and running under the road for about twenty yards or so. In it are small lenses of bluestone, wedging out towards Hen Waith, but those who wish to sample the experience of walking along a mine drive can here do so conveniently, and at no risk.
Finally, what does the future hold for this huge area? Mr. Sidney Taylor, speaking during the discussion on Mr. Manning's paper, said that copper ore of sub economic grade undoubtedly exists ; and the shear zones which control mineralisation may persist in depth. He thought that prospecting in the area surrounding the mines, for deposits which do not reach the surface, or suboutcropping deposits as such are termed, is likely to be rewarding.
Improvement of the precipitation process at Dyffryn Adda is in progress. By increasing the water flow and exposing fresh ore faces the present yield could probably be raised. The current rate of flow of copper-bearing water is 150-200 gallons per minute, averaging 70 parts per million copper, of which 55 parts per million are being recovered. Clearly then, those who should know have faith in the future possibilities of this area. Who, I wonder, will provide the risk capital with which to test their faith ? Much more could he said about the mines themselves, let alone the auxiliary processes dependent upon them. Indeed, these latter could well form the subject of another paper. However, if I have succeeded in presenting the modern viewpoint on these fascinating old works, and, at the same time, in placing on record the story of some of the old ruinous walls on the mountain, I shall feel amply repaid. But I cannot conclude without expressing my deep sense of gratitude to both Mr. W. Manning and to the Institution of Mining and Metallurgy for permission not only to quote from his Paper, but also to use several of the figures illustrating it, namely, Figs. 1, 2 and 3. The Institution have most kindly loaned the necessary blocks to the Society without charge, and it is a pleasure to acknowledge their great kindness in so doing.