All about Haytor
Details of a forthcoming guided tour - and an exclusive excerpt from Josephine Collingwood's best-selling book describes the geology of this popular tor
Josephine Collingwood was Widecombe History Group’s guest speaker in August 2022 - and she captivated a large audience with a whistlestop tour of billions of years of geology. It is perhaps a tribute to her remarkable facility to make some fairly complex and difficult ideas easily accessible and understood that someone at the end asked “ Is this all based on science?”. In fact Josephine spent over two years delving into a wide variety of scientific publications before producing her own graphics - which illustrate the deep time processes that have resulted in the Dartmoor that we know today.
Augmented with photographs of numerous locations from all around Dartmoor, ‘Geology of Dartmoor’ is a beautiful and extremely useful volume. Highly recommended for both the layman and those with some specialist knowledge. This is likely to become ‘the’ go to guide for anyone wanting to understand more about the Dartmoor landscape - and has plenty of suggestions about where to go and what to look for.
The following brief excerpt illustrates the approach taken, featuring one of the best known tors on the Moor:
Haytor Rocks is perhaps the most famous and frequently visited tor in all of Dartmoor, photographed in Figure 10.39. For good reason; it is massive, easily accessed and has spectacular views. There are two enormous stacks divided by a wide avenue of close-cropped grass.
The granite here is coarse grained with megacrysts of feldspar typical of the ‘roof complex’ of the Dartmoor pluton. The main stack has steps carved into it (Figure 10.40) allowing good access to the summit, which also boasts a fine rock basin, shown in Figure 10.41 [and explained on page 91].
The vast stack west of the main Haytor Rocks is known as Low Man and it is on its north west face that geology takes centre stage. The rock face is over 35 m high and shows coarse tor granite overlying the finer grained quarry granite. The quarry granite has eroded more quickly creating an overhang at the interface, shown as the dashed line in Figure 10.42. The fine grained nature of the quarry granite is shown in the close up of Figure 10.43.
The large ‘chip-like’ orthoclase feldspars dominate the exposed rocks of Haytor and often show a sense of alignment (shown in Figure 10.44). This is due to the cooling magma still retaining some viscosity before it was ‘locked-up’ by complete crystallisation.
The quarry granite was extracted extensively for nearly 100 years from 1820 from the nearby quarries. The best quarry to visit is north east of Haytor Rocks, shown in Figure 10.45.
This excerpt from ‘Geology of Dartmoor’ appears by kind permission of Josephine Collingwood. Copyright of all text and photographs remains with the author.
Geology of Dartmoor is available directly from Tavicinity Publishing at a discount. If you are in Widecome-in the-Moor the Cafe on the Green stocks copies, along with other books by Josephine Collingwood and her popular posters.
To learn more about Haytor, why not join the History Group on its next outing on Saturday 18th May 2024?
Enjoy a day out on Haytor Downs in the company of a knowledgeable guide.
Widecombe History Group has arranged a morning and afternoon walk on Haytor Downs with Phil Newman as our Guide. Phil is an Archaeological Landscape investigator who has research and surveyed many sites in the South-West, with a particular interest in mines and quarries.
We will meet at 10:30 at the Saddle Tor car park (what3words///curious.freedom.ideals). Everyone is welcome, but a heads up to Helen on hsbarrow@uwclub.net would be appreciated, so she has an idea of how many to expect. A small charge of £3 will be collected on the day to cover costs.
There will be two walks, one in the morning, then a break for a picnic lunch, and then another afternoon walk. For those of you who can only make the morning walk, Phil can direct you back to the car park from our lunch spot.
The morning walk will take in the quarries at Harrow Barrow and Emsworthy Rocks, then onto Holwell Quarry where we stop for lunch. After lunch (please bring along your own picnic) we will follow the tramway from Holwell to the large main quarry and from there double back to Rubble Heap Quarry. After we have explored Rubble Heap we head back via footpaths to arrivej at the cars at 4 to 4:30 PM.
The total distance covered will be about 3.5miles. We will keep to the well marked paths as much as possible, but uneven or rough ground is very likely. Suitable walking footwear and a waterproof jacket are pretty essential even in May up here on Dartmoor.
The main focus of the walk will be the history and archaeology of the quarrying industry and the Templer Family who founded the quarries and the transport system developed to shift the granite off the Moor. However, Phil will also point out other prehistoric and medieval archaeological sites as we pass them.