A collection of walks, discoveries, insights and pictures of exploring Dartmoor National Park
August 19, 2020
CANTRELL (processing plant) TO REDLAKE (clay extraction) – A JOURNEY FOLLOWING THE TRAMWAY & PIPELINE
This post relates to the Tramway and Clay pipeline which extend from Cantrell, just outside Ivybridge, through to these two the Red Lake and Left Lake clay extraction locations.
The Tramway:
The tramway was first surveyed in 1909 by R. Hansford-Worth to ascertain the feasibility of connecting Red Lake to transport links and hence the outside world. There had been around 4 years opposition to the venture as one might imagine including legal action. The protests included a Dartmoor Preservation Association protest in 1910. The construction of the tramway started in the latter half of 1910 with a gang of around 30 men. Initially, a temporary 2ft gauge track was laid, whilst the track bed itself was prepared. The final gauge of the line was 3ft. The sleepers were made of English oak and the rails were “fixed down” with bolts, clips and dog spikes. Ballast was provided by means of a quarry below Western Beacon, with a supplementary stone crusher at Three Barrows. For the record, 550 tonnes of rail were used alongside 16,000 oak sleepers.
The tramway construction was rapid, thanks to the course selected and it was officially opened on 11th September 1911 (albeit not 100% of the track had at that time been laid). It was finally completed in November 1911.
Rail to sleeper fixing, which looks like a possible dog spike. It is just over 10cm (4in) long
The Pipeline:
The Greenhill Micas complex was the initial clay processing section about a mile or so south of Red Lake. Greenhill is higher than the clay operation at Redlake and the author believes that this “hill” would have presented both a problem and ultimately the solution to the clay men in their desire to create a “gravity” fed pipeline to Cantrell some 8 miles away. Although not documented as such, it is theorised that the hill was chosen as the pre-processing complex rather than a location closer to Redlake. It not only provides natural contours for the process (ie dispensing filtered clay from one process to the next) but also the obvious place to start their “gravity” fed pipeline as from this point it is all downhill to Cantrell. The clay would have had the consistency of cream and was fed into a twin stoneware pipe system, relying solely on the 1000 ft height drop to Cantrell.
The pipeline today can be followed all the way from Greenhill Micas to the top of the incline plane above Cantrell. Along its route would have been 80 inspection points (only 76 are extant today with numbers 77-80 being cleared beside the incline plane). The pipeline was for much of its length buried just below the surface but three concrete bridges and some platforms were required at various points along its route due to the nature of the terrain. When the pipeline was first completed around late 1913, it was discovered that for approx. one third its length, it had water ingress and thus joints had to be dug up and had to be re-worked. This caused months of delay and ultimately Handsford-Worth his job (as he had supervised the pipeline contract).
Sketch map showing the full extent of the operation from Cantrell to Red Lake, a distance of nearly 9 miles
The southern end of the route, from Cantrell to Sharp Tor. The black squares are the pipeline inspection points, which follow (approximately) the course of the tramway. The tramway was first surveyed in 1909 by R. Hansford-Worth and was officially opened on 11th September 1911
Cantrell. The chimney was for the two pan dry kilns. The vertical brick columns were the outer part of two linhays. The loading platform was used to load the refined clay onto Railway wagons.
Cantrell. Originally there were 12 settling tanks here (line of buildings with pitched roofs). Now there are only 10.
Top of the incline plane. Wagons were raised and lowered down to Cantrell here. It is also the place where the clay pipeline left the moor. The final inspection point 76 is nearby. Inspection points 77-80 are now gone.
Clay Pipeline inspection points 73-76
Locomotive shed.
Locomotive C.A. Hansen with a train load of coal or sand, standing on the loop line at the head of the incline. The building is the winding house
Raised bank on tramway. Not really necessary but highly likely the surveyor (Hansford Worth) insisted on this to protect the Addicombe huts immediately to the west. This attention to detail becomes more acute when you see the pipeline passes the other side of the huts.
Northern end of the tramway and pipeline from Sharp Tor area to Red Lake
View from Inspection point 39, to Sharp Tor, the Erme Valley and Stalldown Barrow.
Inspection point 33 near Sharp Tor
Concrete casing of pipeline on the slopes of Sharp Tor
Pipeline concrete encasement at Sharp Tor
The tramway approaching Three Barrows.
Embankment under Three Barrows
Clay Pipeline inspection points 31-36
Inspection point 30, high above the Erme
Clay Pipeline inspection points 25-30
Broken pipeline
Leftlake mica and sand drags
The stoneware pipeline was washed out with water for 15 minutes before clay was fed into it. Apparently, the clay sometimes froze and was unable to be washed out. At Leftlake, the pipeline disappears underground near the brick-built bridge and the author suspects that it is an integral part of that construction. At Leftlake (from 1922), the clay from that operation entered the pipeline. The two sources of clay were never mixed as that at Leftlake was considered inferior quality. The point where the Leftlake clay was added appear to be at the 22nd Inspection point from Greenhill. It is unfortunate that the pipeline is on the opposite side to the tramway from the Leftlake micas, so one assumes a temporary pipe laid across the track when the clay feed was being used.
Clay Pipeline inspection points 19-24
Leftlake bridge, which carried both the tramway and the clay pipeline
Leftlake workings from on top of spoil heap
Concrete structure across track just north of Leftlake
Unknown building alongside track just north of Leftlake
Flooded track heading towards Quickbeam Hill
Concrete encased conduit after 5 miles and 45 chains. SX64539 63881Clay Pipeline inspection points 13-18
Pipeline concrete bridge near Quickbeam Hill. Another concrete bridge for the pipeline. SX65101 64510. This bridge has 10 arches.
Pipeline concrete bridge at Quickbeam Hill
This is the third concrete bridge carrying the twin pipes. 6 miles and 65 chains. It is at GR SX65226 65073
Clay eye’s view
Broken Pipe
Clay Pipeline inspection points 7-12
Embankment at Greenhill Micas. 6 miles and 70 chains from the locomotive shed
Clay Pipeline inspection points 1-6
Part of the Greenhill Micas complex
Brick at Greenhill Micas
Red Lake Cottage
Explosives Hut
Quickbeam Quarry
Final peat cutting before Red Lake
Digging the final cutting, circa 1911. Note the double flanged wagon wheels.
The gang who built the tramway
The two reservoirs at Red Lake. The left one collected water from the boundary leat, the right one was recycled water from Greenhill micas
Foundations of the Winding Engine, the flooded pit and the sky tip
paul November 21, 2020
Great post Steve