Site Records

SiteName:Nenthead: Brewery Shaft & The Nent Force Level

OS Grid Ref: NY78184350

Sub Brit site visit June 1997

[Source: Nick Catford & Paul Thorne]

The Royal Hospital for Seamen at Greenwich acquired the Alston Moor Mines from the Crown in 1735 and began driving the Rampgill Horse (Low) Level the following year. The London Lead Company took over the lease on the Rampgill Vein in 1756 recommencing work on the Horse Level in 1778.

The entrance to the level after quarrying had destroyed the original portal

Two years earlier, work had started on driving the Nent Force Level from Alston. It was originally driven at a width of 3' 6" but this was, in 1777, enlarged to 8' square so that it could be used as a canal to carry out waste rock from the mines it intersected.

In the 19th century, the canal part of the level proved useful as a tourist attraction. By 1805 the level had been driven just over 2 miles and it was estimated that the remaining 5000 yards to Nenthead would take a further 36 years to drive. Throughout its length, the level followed the line of the River Nent.

By 1815 it became uneconomical to continue the level at the original altitude of 890 feet and the eastern continuation from Nentsberry Shaft was 270 feet higher. The level to Rampgill Vein and the 328 feet deep Brewery Shaft was completed in May 1839 and was commemorated by a stone plaque above the portal in Alston. (The plaque is now stored in the town hall). An extension from Brewery Shaft to the Low Whimsey Shaft on Rampgill Vein was driven in the 20th Century by the Belgian Vielle Montagne Zinc Company who bought the leases in 1896.

Photo:Looking down Brewery Shaft from Rampgill Level
Photo by Nick Catford

The VM Company's success was due in part to the introduction of modern machinery driven by compressed air.

Initially the air was supplied by a steam powered compressor plant but between 1803 and 1915 the steam plant was gradually replaced by a system of hydraulic compressors using water from three local reservoirs, Smallcleugh Dam, Perry's Dam and Coalcleugh Dam. One set of compressors was located in a chamber excavated at the base of Brewery Shaft. Water from Smallcleugh Dam was carried in a 12" iron pipe (much of which is still visible on the moor) to the top of a 90 foot tower above the shaft. At the top of the shaft, air was admitted into the feed pipe and was sucked down by the descending water. At the bottom of the shaft the air was collected in a bell shaped air receiver. The escaping water was led up a pipe to the Rampgill Horse Level 260 feet above and compressed the air in the receiver. This water was then directed back down the shaft by a third pipe to turn the 80 and 140 horsepower Pelton Wheels in the engine chambers.

These wheels drove air compressors and an electric generator. The outflowing water was discharged along the Nentforce Level. The compressed air was used for driving drilling and winching machinery, pumping and ventilation. It was carried underground in a complex network of iron pipes. Surplus electricity from the generators was fed to Nenthead Village, the first community in the area to receive an electrical supply.

Survey by Paul Thorne - Drawn by Alan Lawrence

Figure 1 superimposes the shaft plan at Rampgill Level and the shaft bottom. The two sluices leading between Rampgill Low Level and the small reservoir or settling pit, allow some flexibility of water use. Extra water could be fed from the level to power the Pelton wheels if the lower sluice was opened, whilst if too much water was returning up the largest pipe from the separator, then the upper sluice allowed water to overflow into the level.

Photo:Figure 1
Redrwawn by Alan Lawrence from an original drawing by Paul Thorne

The 4" pipe leaving the base of the small reservoir was not seen at the shaft bottom and its purpose needs further examination while travelling in the shaft itself. Approximately half way down the shaft is a stone arched tunnel leading off, perhaps five feet high. This appears to descend steeply out of sight after a short distance. Its purpose is unknown but it may lead to a small shaft which comes out above the waterwheel near the connection to the Nent Force Level.

Further information and pictures about this site continues here

[Source: Nick Catford & Paul Thorne]

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