Croesor quarry - Knowledge (XXG)

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holding some 4.5 million imperial gallons (20 Ml) of water. Local opinion was that a new tunnel, at the level of the lowest chamber, would need to be cut, and a London-based engineer had calculated that pulsometer pumps could empty it in about six months. As the rails on the main incline to the lower chambers were still in place, Kellow mounted a large centrifugal pump on a platform, which he lowered down the rails as water levels fell. It could pump 340,000 imperial gallons (1.5 Ml) per hour, and he drained the entire quarry in around a week. His innovation also covered working practices. Traditionally, Welsh slate mines were worked by teams of four men, consisting of two rockmen, who worked in a chamber below ground, and two mill men, who processed the slate blocks produced by the rockmen. Kellow introduced a new system, in which two-man teams of rockmen supplied slabs to the mill, where independent two-man teams worked, who were allocated slabs by ballot. This enabled the mill to be run at full capacity most of the time, with productivity rising by 25 per cent in the first month after it was introduced. Initial resistance from the quarrymen was overcome as they saw their wages rising significantly.

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an expert in the field of turbines. Kellow's next patent, obtained in 1906, included recycling of the water, which was fed through a 3-inch (7.6 cm) inner flexible pipe, running through the middle of a 5-inch (13 cm) outer pipe, through which the spent water was returned to the sump from which the drill was supplied. Despite the complexity of the hose, the unions which held lengths together were watertight under 900 psi (62 bar). The new design was also much quieter than the old. Next he redesigned the bit, which used a replaceable D-shaped cutter, making it much easier to manufacture than a twist-bit, and this was covered by a patent obtained in 1910. Some water was fed through the drill to lubricate and cool the cutting surfaces. Two further patents from 1914 covered an improved gearbox and a redesigned two-stage reaction turbine, and another in 1915 covered an improved feed cylinder. This supplied the forward thrust to the drill bit, typically 2 to 3 tons for drilling slate, although trials on granite had used up to 20 tons. No data is available for earlier drills, but for the later ones, the turbine ran at 5,000 rpm and the drill at 250 rpm.

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and D Down, working from top to bottom, with floor A at the same level as the main adit. Floors B Up to D Up were connected by an incline that ascended from level A. A second incline descended to floors B Down and C Down, with a separate incline connecting floors C and D Down. Since closure, the chambers below level A, for which there is no natural drainage, have gradually flooded, and the water level has reached the level of the main adit. When the chambers were used for the storage of explosives, a large amount of masonry was installed to house a haulage winch, and this makes it difficult to access the incline to the upper floors.

513:, capable of pumping 400 imperial gallons (1,800 L) per minute. Productivity was improved by the replacement of hand-drills with another of Kellow's inventions. His Kellow drill used high pressure water, produced no dust, and could drill a 7.5-foot (2.3 m) hole in under two minutes, instead of the ten hours required when a hand-drill was used. At the time, percussive drills powered by compressed air were being introduced in many quarries, but Kellow disliked them because they were very noisy, created clouds of dust, and were uncomfortable to the men who had to use them for long periods. His drill was basically a 408: 61: 54: 29: 607:

inaccessible. In spite of a series of collapses, particularly in the Rhosydd quarry, an underground journey from Croesor to Rhosydd is still possible and is considered to be a classic trip for mine explorers. It is known as the Croesor–Rhosydd Through Trip. Fixed ropes, home-made suspension bridges, zip wires, and inflatable boats have been installed which make it possible to complete the journey in comfort although not necessarily in safety.

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following year. At the same time, the Croesor United Slate Company Ltd was set up, with a working capital of £160,000, and a lease to look for slate on Croesor Fawr farm. They also took over the lease held by the Upper company. Hugh Beaver Roberts was in charge of the new company, while Hugh Unsworth McKie was in charge of the Upper company. Both men were directors of the Croesor & Port Madoc Railway, effectively the lower section of the

371:. In order to improve the journey, a long straight road, which now forms part of the A4085, was built south from Garreg by the quarry company. When the Croesor Tramway opened in 1864, a long incline was built from the quarry to the valley floor, and carriage by railway reduced transport costs from 7s 10.5d (39p) per ton to 2s 6.5d (12.5p). The mill was constructed in the early 1860s, and was powered by a 28-foot (8.5 m) diameter 688: 635: 440:, and Kellow, writing in 1911, described four high-pressure turbines, producing 500 hp (370 kW). Water to supply the turbines was obtained from two reservoirs, one located at 1,460 feet (450 m) above sea level and covering 12 acres (4.9 ha), and a second covering 5 acres (2.0 ha) at 1,650 feet (500 m). Water was also taken from a 6-acre (2.4 ha) natural lake at 1,750 feet (530 m). 2222: 599: 517:, similar to those used to drill wood or metal. In order to hold it against the rock face, two small holes were drilled to a depth of 2.5 inches (6.4 cm), into which two rods on the drill were inserted, and jacked apart to secure it. The drill was powered by a small Pelton wheel, supplied with water at 500 psi (34 bar), equivalent to a head of 1,100 feet (340 m). He obtained a 2233: 2988: 2245: 1698: 376:(9.7 kW) steam engine. The shafting for the machinery was under the floor, as was a tramway for trucks to remove the cutting waste. A sale notice dating from 1874 indicated that in addition to sawing tables, there were also planing tables, slate dressing machines, two 12 hp (8.9 kW) steam locomotives and stables. The locomotives were 1686: 622:, called the "Glanypwll Trap". The veins are the New or Deep Vein, the Old Vein, the Small Vein, the Back Vein and the North Vein. At Croesor, the Old Vein is accessible, and dips downwards at about 27 degrees. It is around 120 feet (37 m) wide, at right angles to the bedding plane, and over 330 feet (100 m) horizontally. 444: 472:, but was unable to find British manufacturers who thought it was sensible, or who would make equipment to work with it. He produced a full specification for a three-phase plant in 1902, and toured Europe, talking to electrical manufacturers, who he found more supportive of his plans. He bought the equipment from 496:

main adit, he introduced a 30 hp (22 kW) mining locomotive, the first electric locomotive to work in Wales. It was a 4-wheel design, picking up power from an overhead wire, and is thought to have been built in the quarry workshops. The Pelton wheels were supplied by Gilbert Gilkes and Company Ltd of

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Blaencwm power station continued in operation after the quarry closed, supplying electricity to the national grid until the 1950s, when it was closed. The dam on Llyn Cwm-y-foel was breached, much of the pipeline was removed, and the building became an outdoor pursuits centre. In 1999, National Power

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Kellow was known as a "fearless innovator", and set about modernising the quarry operation. The first problem that he faced was that the quarry below the level of the main adit had filled with water in the 17 years that it had been closed. Twelve chambers were submerged, and there were two sumps each

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between 1898 and 1915. It could drill a 7.5-foot (2.3 m) hole in the slate in under two minutes, much less than the day required using hand drills. The mine was ventilated by a Guibal fan, housed in a fan-house near the entrance to the adit. Peak output under Kellow's direction was between 5,000

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was used, and a large fan house was constructed near the entrance to the adit. It housed a Guibal fan, although described by Richards as a Guiblas fan, and experiments were also carried out with water blast ventilation, using a vertical shaft between the chambers and the hillside. The Guibal fan was

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Croesor is notable amongst Welsh slate quarries for being almost entirely underground, with no significant surface workings. It was rare in its extensive use of forced air ventilation instead of the more common natural ventilation used in most slate mines. It also generated relatively small external

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The main adit was relatively large, and ran for 440 yards (400 m) to reach an underground marshalling area. A vertical shaft, cut downwards through the rock above, enters the adit part way along its length. The quarry was worked on seven floors, designated as D Up, C Up, B Up, A, B Down, C Down

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Croesor is connected to the nearby Rhosydd quarry by a tunnel that was built to aid surveying and settle boundary disputes. Apart from Chamber 1 East, a huge chamber in which the roof has collapsed, most of the accessible mine is in reasonable condition. Below the adit level, the mine is flooded and

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4-wheeled diesel mechanical locomotives, originally built in 1939 and 1941, and obtained second-hand. Two had been scrapped or sold by 1955, and the date of disposal of the third is unknown. Several buildings were constructed in the marshalling area at the far end of the adit, and a massive haulage

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Kellow later collaborated with Gilbert Gilkes on improved designs for his drills, and Gilkes later became a director of the Kellow Rock Drill Syndicate Ltd, set up in 1908, but they parted company because Gilkes thought that Kellow was too much of a perfectionist, unwilling to listen to advice from

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the company, and create The Croesor Slate Company, to take over. However, the machinery was removed, and attempts were made to sell the quarry in April and July 1875. With so much development work, and little good quality rock, the undertaking was not economic. In 1868, the cost of producing slates

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arc lamps, and he installed reversible winches, which were driven by 10 hp (7.5 kW) motors. They could raise 3-ton blocks, when they were being loaded onto trucks, and had a high speed mode, which was used when the blocks were dragged across the floor. For the haulage of trucks along the

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was encountered. Beaumont, Appleby & Ashwell were replaced by the Machine Tunnelling Company, and in June 1872, by the Diamond Rock-boring Company. The work was hampered by water flowing into the mine faster than it could be pumped out, and in 1873 the shareholders declined to advance any more

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Two companies were working the slate by 1861, the Croesor Fawr Slate Quarrying Company Ltd, and the Upper Croesor Slate Quarry Company Ltd. There was close cooperation between them, as in 1865, the Upper company allowed the Fawr company to tip slate waste on their land, and they amalgamated in the

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The Kellow Rock Drill Syndicate converted the original slate mill, dating from 1861, into a workshop called Keldril Works, where the drills were made. It was about 55 by 45 feet (17 by 14 m), but burnt down between 1910 and 1912. The insurance company wrote off the machinery, as the roof had

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Details of the next period are sketchy, although Boyd states that the quarry was bought by S Pope of Llanbedr on 7 July 1883, and became part of the Parc & Croesor Slate Quarries Company Ltd, which was formed on 21 August 1895. The amalgamation with the Park Quarry, which was located near the

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in the 1870s. The quarry had been managed by Thomas Williams of Bryn, Croesor for many years, and Kellow had married Williams' daughter Nell in 1892. Williams died around 1895, and Kellow took over the management of the quarry, having had plans to reopen it for some years. Parc Quarry made slate

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After initial experiments with electricity in the late 1890s, Kellow planned the electrification of the quarry in 1901. By utilising the reservoir in the Cwm Foel valley, located at 1,460 feet (450 m) above sea level, and siting the generating station near the foot of the incline up to the

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In 1895, the quarry reopened under the direction of Moses Kellow, a fearless innovator who set about modernising working practices and methods. The two-man teams working in the mill were no longer tied to a two-man team working underground, which enabled the mill to operate more efficiently.

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which drove about 12 slate saws. In 1866, the mill was extended, to provide another 12 or 14 saws. Power came from another water wheel, constructed underground, and fed by the tailrace of the first wheel. It was 39 feet (12 m) in diameter, and backup power was provided by a 13 hp

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Hydro refurbished it as part of a £1 million project, which included the provision of a new underground pipeline from the reservoir, and underground cables to connect it to the national grid. It is capable of generating 500 kW, and the work was carried out as part of the government's

559:, became aware of this use, and calculated that if there was an explosion underground, either of their two dams could be damaged. They therefore drained both reservoirs, and Cookes began removing about 250 tons of explosives per week, which were taken to Penrhyndeudraeth or by rail from 585:

In the early 1970s the quarry was purchased by the Ffestiniog Slate Company with a view to reopening it as a working slate mine. Planning permission for this was not granted and in the later 1970s most of the remaining mine infrastructure was removed for use in the

436:. He also decided to construct a low-level adit, and work began on it, using the new air drills. A section of incline was built, to be used to counterbalance the trucks removing the spoil, but the adit was not completed. The water wheels were supplemented by 360:. They had a working capital of £45,000, but despite the expertise of Thomas Williams, the new manager who has previously managed the Penrhyn quarry, the company failed. The date is uncertain, as Boyd quotes December 1882, while Richards quotes 1878. 521:

for the design in 1898, the year in which he introduced the drills to the quarry. The drills were still noisy, and discharged the spent water into the quarry, typically 400 imperial gallons (1,800 L) in the 90 seconds it took to drill a hole.

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Output in the early years was quite low, but following Kellow's innovations, was between 5,000 and 6,000 tons per year but then declined until the quarry closed. At its peak, around 300 men were employed there, of whom some 70 stayed in barracks.

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recommended by British manufacturers. He obtained motors from Prague, which were used to drive winches and an electric locomotive, the first to work in Wales. The water wheels were supplemented by Pelton wheels, supplied by Gilbert Gilkes of

246:. Much money was invested in development work, but volumes of useful slate produced were small, amounting to just 226 tons in 1868. Access to the underground workings was by a single adit, and the surface mill was powered by two 355:

In December 1875, the Croesor New Slate Company Ltd took over the workings, eight cottages for the quarrymen, the workshops, and the incline which connected the quarry to the Croesor Tramway, and hence to the slate wharves at

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fallen onto it, but all of it was subsequently rescued from the wreckage. Some of it was moved to the old fitting shop, and some to the Blaencwm power station, where it continued to be used until the quarry closed in 1930.

488:, providing good voltage regulation, and it provided enough spare power to light and heat his house. Power was generated at just below 3000 volts, and transformed down to 220 volts between phases at the point of use. 508:

Other innovations included a new type of planing machine which he invented, which worked between six and ten times faster than traditional designs. Removal of water form the mine was improved by the installation of

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Kellow's Blaencwm power station, once again generating power after a period as an outdoor pursuits centre. The incline to the right led to two further inclines, one to Croesor and the other to Rhosydd.

294:. Both lakes were drained until the explosives had been removed. The quarry was worked on seven levels, but the three below the adit level are now flooded. There was an underground link to the nearby 728:

by Guibal in 1862, and its spiral case which surrounded the fan blades made it much superior to previous open-fan designs. Such fans were used extensively for mine ventilation throughout Britain.

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for such work, but Kellow thought this was too high for distribution underground, and the cost of cabling for a lower voltage system was prohibitive. He found references to a new system of

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Slate was quarried on a small scale at Croesor from around 1840, and the Croicer Valley & Portmadoc Freehold Slate Company Ltd was set up soon afterwards, but did not last for long.

1432: 242:. Small scale quarrying began in the 1846, and by 1861, there were two companies in operation. They amalgamated in 1865, a year after the quarry was connected to the newly opened 338:, worked on a contract to cut shafts and tunnels. The rock found was of poor quality, but hopeful that a slate vein of "paying quality" might yet be found, the directors issued 416:

Garreg Hylldrem inclines further down the Croesor valley, was arranged by Moses Kellow, whose uncle, Joseph Kellow, had briefly been the agent and quarry engineer for the

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ridging, and the amalgamation was made so that rather than supplying the ridging with slates from other quarries, he could supply it with slates from his own quarry.

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waste tips compared with the volume of finished slates produced; this was largely achieved by back-filling underground chambers with waste once they were exhausted.

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to raise additional money to fund the 110 men who were engaged on the development work. Progress below ground was slow, as a band of hard

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The chambers were used by Cookes Explosives to store propellants from the late 1940s until the early 1970s. This ceased when the

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was nine times greater than at Penrhyn Quarry, and whereas they produced 9,000 tons a month, Croesor only produced 226 tons.

1890: 407: 2268: 1765: 1728: 1296: 154: 1358: 2333: 1755: 1552: 720: 381: 2035: 1557: 1522: 250:. A change of ownership in 1875 did little to improve the profitability of the quarry, and it closed in 1878 or 1882. 2807: 1788: 1562: 1542: 1537: 1507: 1502: 572: 466: 263: 2931: 2551: 2202: 1870: 1826: 2225: 2099: 1991: 1885: 1721: 1660: 1532: 1517: 556: 291: 2570: 2413: 1851: 2926: 2836: 2693: 2688: 2668: 2291: 1921: 1905: 1856: 1841: 1547: 2936: 2861: 2841: 298:, and the "Croesor Rhosydd Through Trip" is a well known, if somewhat dangerous, route for mine explorers. 2856: 2323: 2064: 1981: 1900: 1577: 1455: 1441: 546:, who used its underground chambers to store explosives, mainly propellants. The adit was worked by three 2961: 2956: 2742: 2614: 2477: 323:

at Carreg-hylldrem. The Managing Director of the new company was James Wyatt, formerly the agent for the

2797: 2737: 2590: 2511: 2506: 2447: 2383: 2348: 1942: 1895: 1512: 485: 432:, which were fed by a small water-powered compressor located near the foot of the incline to the nearby 2757: 2747: 2703: 2575: 2452: 2951: 2846: 2683: 3019: 2890: 2851: 2831: 2752: 2629: 2496: 2109: 1846: 1655: 576: 2802: 2609: 28: 2921: 2787: 2777: 2624: 2580: 2536: 2343: 2094: 1937: 1336: 547: 480:. It consisted of a 250kVa alternator, which he would couple to a 375 hp pelton wheel impulse 469: 447:

The quarry in 2007, showing the remains of the fan house by the main adit and the site of the mill.

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and 6,000 tons per year, though it declined in the later years, until the quarry closed in 1930.

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The Ffestiniog region contains five major slate veins, which are on top of a thick layer of

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became aware of it, and feared that an underground explosion would damage the dams of the

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Prior to the opening of the Croesor Tramway, slate was carried by horse and cart to

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St. Clair: Nineteenth-Century Coal Town's Experience with a Disaster-Prone Industry

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winch partially blocked access to the incline to the levels above. In 1971, the

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vertical-boilered tank engines with vertical cylinders, manufactured by

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quarry, he obtained a head of 860 feet (260 m) to drive his large

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Between 1868 and 1869, Beaumont, Appleby & Ashwell, a company from

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Final and most awkward crossing in the Croesor to Rhosydd through trip

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turbines. Standard British practice at the time was to use 550-volt

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Industrial and Independent Locomotives and Railways of North Wales

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programme. The power station was formally opened by local

500:, as were the ones which supplemented the water wheels. 699: 646: 1335:. Adventure World Wide. September 2008. Archived from 484:. A separate 25 hp impulse turbine supplied the 2899: 2870: 2821: 2766: 2712: 2643: 2599: 2560: 2486: 2427: 2298: 2195: 2173: 2153: 2087: 2078: 2057: 2048: 2023: 2014: 1964: 1955: 1930: 1914: 1878: 1869: 1834: 1825: 1816: 1764: 1648: 1627: 1591: 1495: 1469: 1448: 210: 195: 190: 180: 170: 165: 119: 105: 95: 84: 42: 33:The quarry in 2014, showing its close proximity to 762:was built which connected various quarries in the 1482:Portmadoc, Beddgelert and South Snowdon Railway 1361:. ukBouldering.com. 2 June 2002. Archived from 1297:"Rebirth of Historic North Wales Power Station" 836:The Autobiography of the Croesor Quarry Manager 1264: 1048: 779:Narrow Gauge Railways in South Caernarvonshire 590:, also owned by the Ffestiniog Slate Company. 491:The quarry was lit by electricity, using 2000- 2276: 1729: 1426: 1111: 1109: 1107: 1105: 1017: 1015: 834:Kellow, Moses (2015). Woodhead, Cathy (ed.). 8: 21: 1316: 1314: 1044: 1042: 855:A History of the North Wales Slate Industry 742:The quarry's produce were distributed from 2283: 2269: 2261: 2084: 2054: 2020: 1961: 1875: 1831: 1822: 1736: 1722: 1714: 1433: 1419: 1411: 37:, with which it interconnects underground. 20: 1174: 1172: 799:(54: Autumn). Ffestiniog Railway Society. 382: 1390: 1378: 1320: 1283: 1163: 1021: 978: 976: 914:The Slate Regions of North and Mid Wales 1402: 1248: 1246: 1115: 1084: 1072: 1033: 972: 786:Bradley, V J; Hindley, P, eds. (1968). 557:Ffestiniog pumped storage power station 292:Ffestiniog pumped storage power station 1237: 1225: 1213: 1201: 1189: 1178: 1151: 1139: 1127: 1096: 895:A Gazeteer of the Welsh Slate Industry 60: 7: 1299:. The Free Library. 26 November 1999 1060: 1006: 994: 982: 553:Central Electricity Generating Board 288:Central Electricity Generating Board 1671:Welsh Highland Railway (Caernarfon) 1252: 875:Croesor Rhosydd - The Through Trip 561:Blaenau Ffestiniog railway station 14: 1477:North Wales Narrow Gauge Railways 16:Disused slate mine in North Wales 2986: 2243: 2231: 2221: 2220: 1696: 1684: 686: 633: 347:money. The Directors decided to 59: 52: 27: 1666:Welsh Highland Heritage Railway 872:Moulding, Miles (2 July 2006). 823:Kellow, Moses (February 1911). 1766:Distribution network operators 1635:Welsh Highland Railway Limited 1359:"Croesor Rhosydd Through Trip" 952:Weaver, Rodney (August 1978). 795:FRS (1971). "Gwynedd Topics". 1: 931:Wallace, Anthony F C (1988). 826:The Park and Croesor Quarries 790:. Birmingham Locomotive Club. 567:works in the United Kingdom. 428:Kellow introduced compressed 1756:Energy in the United Kingdom 937:. Cornell University Press. 912:Richards, Alun John (1999). 893:Richards, Alun John (1991). 797:Ffestiniog Railway Magazine 3036: 1789:Western Power Distribution 1563:Porthmadog cross town link 1265:Bradley & Hindley 1968 1049:Bradley & Hindley 1968 829:. The Slate Trade Gazette. 735: 2980: 2216: 2203:Renewable energy in Wales 1751: 1679: 1640:Festiniog Railway Company 555:(CEGB), operators of the 538:Following the end of the 262:station, which generated 47: 26: 2808:Rhiw-goch (Denbighshire) 2354:Fron-Boeth and Pant-Mawr 1333:"The Chamber of Horrors" 838:. Delfryn Publications. 916:. Gwasg Carreg Gwalch. 897:. Gwasg Carreg Gwalch. 804:Hancock, Celia (2006). 230:is a large underground 3015:Slate mines in Gwynedd 2793:Deeside and Moelfferna 1456:Welsh Highland Railway 1442:Welsh Highland Railway 853:Lindsay, Jean (1974). 603: 448: 412: 254:Following trials with 857:. David and Charles. 808:. Adit Publications. 601: 582:on 26 November 1999. 446: 410: 2292:Welsh slate quarries 806:Conglog Slate Quarry 777:Boyd, James (1972). 754:), a harbour on the 548:Ruston & Hornsby 238:which was served by 2932:Frongoch (Aberdyfi) 1578:Gelert's Farm Works 1393:, pp. 137–138. 1365:on 7 February 2012. 1166:, pp. 111–112. 888:on 7 February 2012. 470:alternating current 267:alternating current 137: / 23: 2414:Votty & Bowydd 2300:Blaenau Ffestiniog 1573:Gelert's Farm Halt 1568:Porthmadog Harbour 1063:, pp. 93, 95. 721:Forced ventilation 698:. You can help by 645:. You can help by 604: 594:Current conditions 474:Kolben and Company 449: 413: 369:Ffestiniog Railway 269:, rather than the 185:Underground Quarry 141:52.9910°N 4.0016°W 3002: 3001: 2881:Dandderwen quarry 2694:Rhiw-goch (Conwy) 2571:Bryn Hafod-y-Wern 2258: 2257: 2191: 2190: 2169: 2168: 2074: 2073: 2044: 2043: 2010: 2009: 1951: 1950: 1865: 1864: 1774:National Grid plc 1711: 1710: 1339:on 22 August 2012 1192:, pp. 20–21. 1099:, pp. 18–19. 997:, pp. 94–95. 944:978-0-8014-9900-5 923:978-0-86381-552-2 904:978-0-86381-196-8 864:978-0-7153-6265-5 845:978-0-9561469-9-1 815:978-0-9522979-4-9 716: 715: 663: 662: 563:to various other 534:Reuse for storage 511:centrifugal pumps 225: 224: 3027: 2993:Wales portal 2991: 2990: 2989: 2689:Prince Llewellyn 2552:Rhiw'r Gwreiddyn 2285: 2278: 2271: 2262: 2248: 2247: 2246: 2236: 2235: 2224: 2223: 2085: 2055: 2021: 1962: 1876: 1832: 1823: 1738: 1731: 1724: 1715: 1701: 1700: 1699: 1689: 1688: 1435: 1428: 1421: 1412: 1406: 1400: 1394: 1388: 1382: 1376: 1367: 1366: 1355: 1349: 1348: 1346: 1344: 1329: 1323: 1318: 1309: 1308: 1306: 1304: 1293: 1287: 1281: 1268: 1262: 1256: 1250: 1241: 1235: 1229: 1223: 1217: 1211: 1205: 1199: 1193: 1187: 1181: 1176: 1167: 1161: 1155: 1149: 1143: 1137: 1131: 1125: 1119: 1113: 1100: 1094: 1088: 1082: 1076: 1070: 1064: 1058: 1052: 1046: 1037: 1031: 1025: 1019: 1010: 1004: 998: 992: 986: 985:, pp. 93–94 980: 962: 960: 955:The Kellow Drill 948: 927: 908: 889: 887: 881:. Archived from 880: 868: 849: 830: 819: 800: 791: 782: 781:. Oakwood Press. 711: 708: 690: 683: 670:Unusual Features 658: 655: 637: 630: 573:renewable energy 544:Penrhyndeudraeth 540:Second World War 386: 384: 365:Penrhyndeudraeth 221: 219: 206: 204: 161: 152: 151: 149: 148: 147: 146:52.9910; -4.0016 142: 138: 135: 134: 133: 130: 63: 62: 56: 31: 24: 3035: 3034: 3030: 3029: 3028: 3026: 3025: 3024: 3005: 3004: 3003: 2998: 2987: 2985: 2976: 2937:Frongoch (Bala) 2895: 2891:LLangolman Farm 2866: 2817: 2762: 2708: 2669:Clogwyn y Fuwch 2651: 2639: 2595: 2556: 2482: 2432: 2423: 2324:Bwlch y Slaters 2307: 2294: 2289: 2259: 2254: 2244: 2242: 2230: 2212: 2187: 2165: 2149: 2070: 2040: 2006: 1947: 1926: 1910: 1861: 1812: 1760: 1747: 1745:Energy in Wales 1742: 1712: 1707: 1697: 1695: 1683: 1675: 1644: 1623: 1587: 1491: 1487:Croesor Tramway 1465: 1444: 1439: 1409: 1401: 1397: 1389: 1385: 1377: 1370: 1357: 1356: 1352: 1342: 1340: 1331: 1330: 1326: 1319: 1312: 1302: 1300: 1295: 1294: 1290: 1282: 1271: 1263: 1259: 1251: 1244: 1236: 1232: 1228:, pp. 2–3. 1224: 1220: 1216:, pp. 1–2. 1212: 1208: 1200: 1196: 1188: 1184: 1177: 1170: 1162: 1158: 1150: 1146: 1138: 1134: 1126: 1122: 1114: 1103: 1095: 1091: 1087:, pp. 7–8. 1083: 1079: 1071: 1067: 1059: 1055: 1047: 1040: 1032: 1028: 1020: 1013: 1005: 1001: 993: 989: 981: 974: 970: 965: 958: 951: 945: 930: 924: 911: 905: 892: 885: 878: 871: 865: 852: 846: 833: 822: 816: 803: 794: 785: 776: 772: 760:Croesor Tramway 758:. In 1865, the 756:Glaslyn Estuary 740: 738:Croesor Tramway 734: 712: 706: 703: 696:needs expansion 681: 672: 659: 653: 650: 643:needs expansion 628: 613: 596: 536: 506: 486:exciter circuit 454: 452:Electrification 405: 377: 367:station on the 317:Croesor Tramway 312: 304: 244:Croesor Tramway 240:Croesor Tramway 217: 215: 202: 200: 157: 153: 145: 143: 139: 136: 131: 128: 126: 124: 123: 80: 79: 78: 77: 71: 70: 69: 68: 64: 38: 17: 12: 11: 5: 3033: 3031: 3023: 3022: 3017: 3007: 3006: 3000: 2999: 2997: 2996: 2981: 2978: 2977: 2975: 2974: 2972:Whitland Abbey 2969: 2964: 2959: 2954: 2949: 2944: 2939: 2934: 2929: 2924: 2919: 2914: 2909: 2903: 2901: 2897: 2896: 2894: 2893: 2888: 2886:Gilfach quarry 2883: 2877: 2875: 2868: 2867: 2865: 2864: 2862:Tyddyn-Sieffre 2859: 2854: 2849: 2844: 2842:Cyfannedd Fawr 2839: 2834: 2828: 2826: 2819: 2818: 2816: 2815: 2810: 2805: 2800: 2795: 2790: 2785: 2780: 2774: 2772: 2764: 2763: 2761: 2760: 2755: 2750: 2745: 2740: 2735: 2730: 2725: 2719: 2717: 2714:Nantlle Valley 2710: 2709: 2707: 2706: 2701: 2696: 2691: 2686: 2681: 2676: 2671: 2666: 2661: 2655: 2653: 2641: 2640: 2638: 2637: 2632: 2627: 2622: 2617: 2612: 2606: 2604: 2597: 2596: 2594: 2593: 2588: 2583: 2578: 2573: 2567: 2565: 2558: 2557: 2555: 2554: 2549: 2544: 2539: 2534: 2529: 2524: 2519: 2514: 2509: 2504: 2499: 2493: 2491: 2484: 2483: 2481: 2480: 2475: 2470: 2465: 2460: 2455: 2450: 2448:Coed y Chwarel 2445: 2439: 2437: 2425: 2424: 2422: 2421: 2416: 2411: 2406: 2401: 2396: 2391: 2386: 2384:Nyth-y-Gigfran 2381: 2376: 2371: 2366: 2361: 2356: 2351: 2349:Diphwys Casson 2346: 2341: 2336: 2331: 2326: 2321: 2315: 2313: 2296: 2295: 2290: 2288: 2287: 2280: 2273: 2265: 2256: 2255: 2253: 2252: 2240: 2228: 2217: 2214: 2213: 2211: 2210: 2205: 2199: 2197: 2193: 2192: 2189: 2188: 2186: 2185: 2179: 2177: 2171: 2170: 2167: 2166: 2164: 2163: 2161:Atlantic Array 2157: 2155: 2151: 2150: 2148: 2147: 2142: 2137: 2132: 2127: 2122: 2117: 2112: 2107: 2102: 2100:Brechfa Forest 2097: 2091: 2089: 2082: 2076: 2075: 2072: 2071: 2069: 2068: 2061: 2059: 2052: 2046: 2045: 2042: 2041: 2039: 2038: 2033: 2027: 2025: 2018: 2012: 2011: 2008: 2007: 2005: 2004: 1999: 1994: 1989: 1984: 1979: 1974: 1968: 1966: 1959: 1953: 1952: 1949: 1948: 1946: 1945: 1940: 1934: 1932: 1928: 1927: 1925: 1924: 1918: 1916: 1912: 1911: 1909: 1908: 1903: 1898: 1893: 1888: 1882: 1880: 1873: 1867: 1866: 1863: 1862: 1860: 1859: 1854: 1849: 1844: 1838: 1836: 1829: 1820: 1818:Power stations 1814: 1813: 1811: 1810: 1805: 1804: 1803: 1793: 1792: 1791: 1786: 1781: 1770: 1768: 1762: 1761: 1759: 1758: 1752: 1749: 1748: 1743: 1741: 1740: 1733: 1726: 1718: 1709: 1708: 1706: 1705: 1693: 1680: 1677: 1676: 1674: 1673: 1668: 1663: 1658: 1652: 1650: 1646: 1645: 1643: 1642: 1637: 1631: 1629: 1625: 1624: 1622: 1621: 1616: 1611: 1606: 1601: 1595: 1593: 1589: 1588: 1586: 1585: 1580: 1575: 1570: 1565: 1560: 1555: 1550: 1545: 1540: 1535: 1530: 1528:Snowdon Ranger 1525: 1520: 1515: 1510: 1505: 1499: 1497: 1493: 1492: 1490: 1489: 1484: 1479: 1473: 1471: 1467: 1466: 1464: 1463: 1458: 1452: 1450: 1446: 1445: 1440: 1438: 1437: 1430: 1423: 1415: 1408: 1407: 1395: 1383: 1381:, p. 137. 1368: 1350: 1324: 1310: 1288: 1286:, p. 138. 1269: 1257: 1242: 1230: 1218: 1206: 1194: 1182: 1168: 1156: 1144: 1132: 1120: 1101: 1089: 1077: 1075:, p. 161. 1065: 1053: 1038: 1036:, p. 153. 1026: 1011: 999: 987: 971: 969: 966: 964: 963: 949: 943: 928: 922: 909: 903: 890: 869: 863: 850: 844: 831: 820: 814: 801: 792: 783: 773: 771: 768: 736:Main article: 733: 730: 714: 713: 693: 691: 680: 677: 671: 668: 661: 660: 640: 638: 627: 624: 612: 609: 595: 592: 588:Oakeley Quarry 535: 532: 505: 502: 463:direct current 459:hydro-electric 453: 450: 434:Rhosydd quarry 418:Conglog quarry 404: 401: 325:Penrhyn quarry 311: 308: 303: 300: 296:Rhosydd quarry 271:direct current 260:hydro-electric 228:Croesor quarry 223: 222: 212: 208: 207: 197: 193: 192: 188: 187: 182: 178: 177: 172: 168: 167: 163: 162: 155:grid reference 121: 117: 116: 107: 103: 102: 97: 93: 92: 86: 82: 81: 72: 67:Croesor quarry 66: 65: 58: 57: 51: 50: 49: 48: 45: 44: 40: 39: 35:Rhosydd Quarry 32: 15: 13: 10: 9: 6: 4: 3: 2: 3032: 3021: 3018: 3016: 3013: 3012: 3010: 2995: 2994: 2983: 2982: 2979: 2973: 2970: 2968: 2965: 2963: 2960: 2958: 2955: 2953: 2950: 2948: 2945: 2943: 2940: 2938: 2935: 2933: 2930: 2928: 2925: 2923: 2920: 2918: 2915: 2913: 2910: 2908: 2905: 2904: 2902: 2898: 2892: 2889: 2887: 2884: 2882: 2879: 2878: 2876: 2873: 2869: 2863: 2860: 2858: 2857:Tan-y-dderwen 2855: 2853: 2850: 2848: 2845: 2843: 2840: 2838: 2835: 2833: 2830: 2829: 2827: 2824: 2820: 2814: 2811: 2809: 2806: 2804: 2801: 2799: 2796: 2794: 2791: 2789: 2786: 2784: 2781: 2779: 2776: 2775: 2773: 2770: 2765: 2759: 2756: 2754: 2753:Pen-yr-Orsedd 2751: 2749: 2746: 2744: 2741: 2739: 2736: 2734: 2731: 2729: 2726: 2724: 2721: 2720: 2718: 2715: 2711: 2705: 2702: 2700: 2697: 2695: 2692: 2690: 2687: 2685: 2682: 2680: 2677: 2675: 2672: 2670: 2667: 2665: 2662: 2660: 2657: 2656: 2654: 2652:valleys areas 2650: 2646: 2642: 2636: 2633: 2631: 2628: 2626: 2623: 2621: 2618: 2616: 2613: 2611: 2608: 2607: 2605: 2602: 2598: 2592: 2589: 2587: 2584: 2582: 2579: 2577: 2574: 2572: 2569: 2568: 2566: 2563: 2559: 2553: 2550: 2548: 2545: 2543: 2540: 2538: 2535: 2533: 2530: 2528: 2525: 2523: 2520: 2518: 2515: 2513: 2510: 2508: 2505: 2503: 2500: 2498: 2497:Abercwmeiddaw 2495: 2494: 2492: 2489: 2485: 2479: 2476: 2474: 2471: 2469: 2466: 2464: 2461: 2459: 2456: 2454: 2451: 2449: 2446: 2444: 2441: 2440: 2438: 2435: 2430: 2429:Dinas Mawddwy 2426: 2420: 2417: 2415: 2412: 2410: 2407: 2405: 2402: 2400: 2397: 2395: 2392: 2390: 2387: 2385: 2382: 2380: 2377: 2375: 2372: 2370: 2367: 2365: 2362: 2360: 2357: 2355: 2352: 2350: 2347: 2345: 2342: 2340: 2337: 2335: 2332: 2330: 2327: 2325: 2322: 2320: 2317: 2316: 2314: 2311: 2310:Cwm Penmachno 2305: 2301: 2297: 2293: 2286: 2281: 2279: 2274: 2272: 2267: 2266: 2263: 2251: 2241: 2239: 2234: 2229: 2227: 2219: 2218: 2215: 2209: 2206: 2204: 2201: 2200: 2198: 2194: 2184: 2181: 2180: 2178: 2176: 2172: 2162: 2159: 2158: 2156: 2152: 2146: 2143: 2141: 2140:Pen y Cymoedd 2138: 2136: 2133: 2131: 2128: 2126: 2125:Mynydd Maendy 2123: 2121: 2120:Moel Maelogan 2118: 2116: 2113: 2111: 2108: 2106: 2103: 2101: 2098: 2096: 2093: 2092: 2090: 2086: 2083: 2081: 2077: 2066: 2063: 2062: 2060: 2056: 2053: 2051: 2047: 2037: 2034: 2032: 2029: 2028: 2026: 2022: 2019: 2017: 2013: 2003: 2000: 1998: 1995: 1993: 1990: 1988: 1985: 1983: 1980: 1978: 1975: 1973: 1970: 1969: 1967: 1963: 1960: 1958: 1957:Hydroelectric 1954: 1944: 1941: 1939: 1936: 1935: 1933: 1929: 1923: 1920: 1919: 1917: 1913: 1907: 1904: 1902: 1899: 1897: 1894: 1892: 1891:Connah's Quay 1889: 1887: 1884: 1883: 1881: 1877: 1874: 1872: 1868: 1858: 1855: 1853: 1850: 1848: 1845: 1843: 1840: 1839: 1837: 1833: 1830: 1828: 1824: 1821: 1819: 1815: 1809: 1808:Vattenfall UK 1806: 1802: 1799: 1798: 1797: 1796:ScottishPower 1794: 1790: 1787: 1785: 1782: 1780: 1777: 1776: 1775: 1772: 1771: 1769: 1767: 1763: 1757: 1754: 1753: 1750: 1746: 1739: 1734: 1732: 1727: 1725: 1720: 1719: 1716: 1704: 1694: 1692: 1687: 1682: 1681: 1678: 1672: 1669: 1667: 1664: 1662: 1659: 1657: 1654: 1653: 1651: 1649:Rolling stock 1647: 1641: 1638: 1636: 1633: 1632: 1630: 1626: 1620: 1617: 1615: 1612: 1610: 1607: 1605: 1602: 1600: 1597: 1596: 1594: 1590: 1584: 1581: 1579: 1576: 1574: 1571: 1569: 1566: 1564: 1561: 1559: 1556: 1554: 1551: 1549: 1546: 1544: 1541: 1539: 1536: 1534: 1531: 1529: 1526: 1524: 1521: 1519: 1516: 1514: 1511: 1509: 1506: 1504: 1501: 1500: 1498: 1494: 1488: 1485: 1483: 1480: 1478: 1475: 1474: 1472: 1468: 1462: 1459: 1457: 1454: 1453: 1451: 1449:Main articles 1447: 1443: 1436: 1431: 1429: 1424: 1422: 1417: 1416: 1413: 1405:, p. 45. 1404: 1399: 1396: 1392: 1391:Richards 1999 1387: 1384: 1380: 1379:Richards 1999 1375: 1373: 1369: 1364: 1360: 1354: 1351: 1338: 1334: 1328: 1325: 1322: 1321:Moulding 2006 1317: 1315: 1311: 1298: 1292: 1289: 1285: 1284:Richards 1999 1280: 1278: 1276: 1274: 1270: 1267:, p. 34. 1266: 1261: 1258: 1254: 1249: 1247: 1243: 1239: 1234: 1231: 1227: 1222: 1219: 1215: 1210: 1207: 1203: 1198: 1195: 1191: 1186: 1183: 1180: 1175: 1173: 1169: 1165: 1164:Richards 1991 1160: 1157: 1154:, p. 20. 1153: 1148: 1145: 1141: 1136: 1133: 1130:, p. 19. 1129: 1124: 1121: 1118:, p. 162 1117: 1112: 1110: 1108: 1106: 1102: 1098: 1093: 1090: 1086: 1081: 1078: 1074: 1069: 1066: 1062: 1057: 1054: 1050: 1045: 1043: 1039: 1035: 1030: 1027: 1024:, p. 111 1023: 1022:Richards 1991 1018: 1016: 1012: 1009:, p. 95. 1008: 1003: 1000: 996: 991: 988: 984: 979: 977: 973: 967: 957: 956: 950: 946: 940: 936: 935: 929: 925: 919: 915: 910: 906: 900: 896: 891: 884: 877: 876: 870: 866: 860: 856: 851: 847: 841: 837: 832: 828: 827: 821: 817: 811: 807: 802: 798: 793: 789: 784: 780: 775: 774: 769: 767: 765: 761: 757: 753: 749: 745: 739: 731: 729: 727: 722: 710: 701: 697: 694:This section 692: 689: 685: 684: 678: 676: 669: 667: 657: 648: 644: 641:This section 639: 636: 632: 631: 625: 623: 621: 618: 610: 608: 600: 593: 591: 589: 583: 581: 578: 574: 568: 566: 562: 558: 554: 549: 545: 541: 533: 531: 527: 523: 520: 516: 512: 503: 501: 499: 494: 489: 487: 483: 479: 475: 471: 468: 464: 460: 451: 445: 441: 439: 438:Pelton wheels 435: 431: 426: 422: 419: 409: 402: 400: 398: 394: 390: 385: 380: 374: 370: 366: 361: 359: 353: 350: 345: 341: 337: 332: 330: 326: 322: 318: 309: 307: 301: 299: 297: 293: 289: 284: 281: 277: 272: 268: 265: 261: 257: 251: 249: 245: 241: 237: 233: 229: 218:December 1930 214:December 1930 213: 209: 198: 194: 189: 186: 183: 179: 176: 173: 169: 164: 160: 156: 150: 122: 118: 115: 111: 108: 104: 101: 98: 94: 91: 87: 83: 76: 55: 46: 41: 36: 30: 25: 19: 2984: 2962:Rhyd-yr-Onen 2957:Penrhyn-gwyn 2743:Nantlle Vale 2615:Chwarel Fawr 2581:Pantdreiniog 2507:Aberllefenni 2488:Dulas Valley 2478:Tal y Mieryn 2344:Cwt y Bugail 2067:(demolished) 1971: 1628:Preservation 1553:Pont Croesor 1403:Wallace 1988 1398: 1386: 1363:the original 1353: 1341:. Retrieved 1337:the original 1327: 1301:. Retrieved 1291: 1260: 1255:, p. 16 1240:, p. 4. 1233: 1221: 1209: 1204:, p. 2. 1197: 1185: 1159: 1147: 1142:, p. 1. 1135: 1123: 1116:Lindsay 1974 1092: 1085:Hancock 2006 1080: 1073:Lindsay 1974 1068: 1056: 1051:, p. 42 1034:Lindsay 1974 1029: 1002: 990: 954: 933: 913: 894: 883:the original 874: 854: 835: 825: 805: 796: 787: 778: 770:Bibliography 751: 741: 724:patented in 717: 704: 700:adding to it 695: 673: 664: 651: 647:adding to it 642: 614: 605: 584: 569: 537: 528: 524: 507: 490: 455: 427: 423: 414: 362: 354: 333: 313: 305: 285: 252: 248:water wheels 227: 226: 73:Location in 18: 3020:Llanfrothen 2912:Bryn Eglwys 2837:Ty'n-y-coed 2798:Moel y Faen 2738:Moel Tryfan 2704:Ty'n-y-bryn 2664:Chwarel Ddu 2591:Tan-y-Bwlch 2458:Gartheiniog 2369:Maenofferen 2319:Blaen y Cwm 2130:North Hoyle 2115:Gwynt y Môr 2031:Trawsfynydd 2002:Swansea Bay 1661:Moel Tryfan 1558:Pen-y-Mount 1523:Plas-y-Nant 1470:Forerunners 1461:Restoration 1238:Weaver 1978 1226:Weaver 1978 1214:Weaver 1978 1202:Weaver 1978 1190:Kellow 2015 1179:Kellow 1911 1152:Kellow 2015 1140:Weaver 1978 1128:Kellow 2015 1097:Kellow 2015 961:. Adit Now. 764:Cwm Croesor 746:(sometimes 626:Description 617:feldspathic 580:Elfyn Llwyd 515:twist drill 493:candlepower 467:three-phase 373:water wheel 310:Early phase 264:three-phase 236:North Wales 144: / 120:Coordinates 3009:Categories 2872:Llangolman 2769:Llangollen 2758:Tal-y-Sarn 2748:Pen-y-Bryn 2674:Cwm Eigiau 2576:Moel Faban 2542:Llwyngwern 2512:Braichgoch 2502:Abercorris 2468:Maesygamfa 2453:Foel Dinas 2443:Cae Abatty 2434:Aberangell 2208:Ynni Cymru 2145:Rhyl Flats 2135:Parc Cynog 2110:Cefn Croes 2080:Wind farms 1992:Ffestiniog 1886:Baglan Bay 1852:Rogerstone 1827:Coal-fired 1604:Fron-Boeth 1583:Porthmadog 1543:Beddgelert 1538:Meillionen 1508:Bontnewydd 1503:Caernarfon 968:References 748:anglisised 744:Porthmadog 707:March 2020 654:March 2020 504:Innovation 430:air drills 403:Late phase 393:Caernarfon 358:Porthmadog 340:debentures 319:below the 256:air drills 232:slate mine 166:Production 129:52°59′28″N 2952:Glyn-lago 2907:Bellstone 2847:Goleuwern 2723:Alexandra 2684:Hafod-Las 2625:Glyrhonwy 2601:Llanberis 2463:Hendreddu 2399:Penmachno 2364:Llechwedd 2359:Graig Ddu 2339:Cwmorthin 2154:Cancelled 2095:Alltwalis 2050:Oil-fired 1997:Maentwrog 1987:Dolgarrog 1871:Gas-fired 1801:SP Manweb 1609:Pant Mawr 1496:Locations 1061:Boyd 1972 1007:Boyd 1972 995:Boyd 1972 983:Boyd 1972 752:Portmadoc 732:Transport 679:Operation 565:ICI Nobel 389:De Winton 132:4°00′06″W 2967:Rosebush 2917:Cwm Ebol 2900:Outliers 2852:Hen-Ddol 2832:Bryngwyn 2783:Cambrian 2767:Vale of 2733:Dorothea 2630:Marchlyn 2620:Dinorwic 2562:Bethesda 2517:Cambergi 2404:Rhiwbach 2226:Category 2065:Pembroke 1982:Dinorwig 1977:Cwm Dyli 1972:Blaencwm 1922:Abernedd 1901:Pembroke 1857:Uskmouth 1842:Aberthaw 1779:Infralec 1592:Quarries 1533:Rhyd Ddu 1518:Waunfawr 1253:FRS 1971 620:porphyry 329:Bethesda 171:Products 159:SH626436 85:Location 43:Location 2947:Gilfach 2927:Dolgoch 2803:Penarth 2728:Cilgwyn 2610:Cefn Du 2586:Penrhyn 2547:Ratgoed 2532:Gaewern 2522:Cymerau 2473:Minllyn 2419:Wrysgan 2409:Rhosydd 2389:Oakeley 2379:Moelwyn 2334:Croesor 2329:Conglog 2304:Croesor 2183:Morlais 2016:Nuclear 1943:Shotton 1896:Deeside 1656:Russell 1619:Rhosydd 1599:Croesor 1548:Nantmor 1343:1 April 1303:1 April 726:Belgium 611:Geology 482:turbine 397:Nantlle 349:wind up 327:, near 321:incline 302:History 280:patents 216: ( 201: ( 191:History 106:Country 100:Gwynedd 90:Croesor 75:Gwynedd 22:Croesor 2942:Glogue 2922:Darren 2823:Arthog 2788:Clogau 2778:Berwyn 2659:Cedryn 2635:Vivian 2537:Hengae 2238:Energy 2088:Active 2058:Closed 2024:Closed 1965:Active 1931:Closed 1915:Future 1906:Severn 1879:Active 1847:Llynfi 1835:Closed 1784:SWALEC 1691:Trains 941: 920: 901: 861: 842: 812: 519:patent 498:Kendal 478:Prague 336:London 276:Kendal 211:Closed 196:Opened 96:County 2813:Wynne 2649:Conwy 2645:Lledr 2436:areas 2374:Manod 2312:areas 2250:Wales 2196:Other 2175:Tidal 2105:Carno 2036:Wylfa 1938:Barry 1703:Wales 1513:Dinas 959:(PDF) 886:(PDF) 879:(PDF) 379:0-4-0 344:chert 175:Slate 110:Wales 88:near 2874:Area 2825:area 2771:area 2716:area 2699:Rhos 2679:Foel 2647:and 2603:area 2564:area 2490:area 2431:and 2394:Parc 2308:and 1614:Parc 1345:2013 1305:2013 939:ISBN 918:ISBN 899:ISBN 859:ISBN 840:ISBN 810:ISBN 203:1846 199:1846 181:Type 2527:Era 750:as 702:. 649:. 476:of 391:of 234:in 3011:: 2302:, 1371:^ 1313:^ 1272:^ 1245:^ 1171:^ 1104:^ 1041:^ 1014:^ 975:^ 577:MP 399:. 383:VB 114:UK 112:, 2306:, 2284:e 2277:t 2270:v 1737:e 1730:t 1723:v 1434:e 1427:t 1420:v 1347:. 1307:. 947:. 926:. 907:. 867:. 848:. 818:. 709:) 705:( 656:) 652:( 220:) 205:)

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Index