Finding the Fremington Clay Erratics
I think I have found two of the original half a dozen, so
they could be examined again and the very old descriptions of them could be
updated.
The original references are:
Dewey, H. (1910). Notes on some igneous rocks from North
Devon. Proceedings of the Geologists' Association, 21(4),
429–434.
Taylor, C.W. (1956) Erratics of the Saunton and Fremington
areas. Report and Transactions of the Devonshire Associaton for the
Advancement of Science, Literature and Art, 88, 52–64.)
There are two boulders from this district which are
mentioned in the literature, and both of them were found without any
difficulty, as they are preserved, and it would appear that enquiries for them
are not infrequent. The present owner of Combrew Farm, Mr. Tucker, is aware of
their interest, and unnecessary "hammering" is discouraged. The third
boulder, which, though mentioned, has not so far been described or figured,
came originally from the clay-pit of the old Fishley Pottery, now long disused,
while as regards recent finds, two further masses have been obtained from the
brown clay of Brannam's pit and are noted below. Although the literature makes
no mention of the fact, the boulders Nos. 6 and 7 following are understood from
local information to have been found also in the clay of the Fishley pit.
No. 6. A boulder is mentioned by Dewey (“a dark grey,
finely crystalline rock with small white porphyritic felspars in the groundmass”)
as at Bickington, about a quarter mile
east of Combrew Farm, but owing to development, it has recently been moved to
the garden on the right of the gateway to the main yard of the Farm. In case
any ultra-zealous Glacialist should fit certain scars on portions of this rock,
the author hastens to mention that it was dragged in its present position
instead of being ruthlessly broken up on site, a consideration which is highly
appreciated.
The original measurements and photograph have been given
by Dewey, which need not be repeated here; it may be added, however, that the
mass shows no distinct striae or wedge-shape, and the boulder measures roughly
40 x 30 x 25 inches high, the longest axis pointing almost E-W. It may be a Cornish
spilite, of the pillow-lava type of igneous rock, which occurs in the Meneage
district and elsewhere in Cornwall.
No. 7. The next erratic of this group is the hyalopilitic
andesite, also previously described with No. 6 above. It is now situated on the
right of the gated portion of the driveway to Combrew Farm, and is a glassy,
brittle andesite, quite different from any of the foregoing rocks. Well rounded
and about sixteen inches across, it contains no augite, but otherwise resembles
similar rocks of Dumfries and Loch Craignish, Argyllshire.
No. 8. The rock from the Fishley Pottery clay-pit has
hitherto merely been mentioned as "an igneous boulder" which may now
be found on the right-hand, inside the gate of the first building (the old
disused pottery) on approaching Combrew Farm from the main road. It is well
covered with lichen, with flat top and base, and measures 47 x 19 x 16 inches
high. Of a light grey colour, it is holocrystalline, with some quartz and much
felspar, which appears altered; little mica could be observed. The texture is
rather granitic, with a fine, pale coloured base containing the larger
phenocrysts of quartz and felspar up to 5 mm. in size, but averaging 3 mm.
Various rocks, maybe the erratics, appear to still be on
the roadside and pictured on Google Streetview.
https://maps.app.goo.gl/VWN42wA1u1PbG6zZ9
https://maps.app.goo.gl/ijcV53LLrDUywAKR8
https://maps.app.goo.gl/mMB82AMYzt4KxPjN7
https://maps.app.goo.gl/8uvFckNu1TB7BFhd6
https://maps.app.goo.gl/iocQpaVFEwAGqQ176
UPDATE – I visited the farm on 2 November 2025 and
photographed and measured the rocks.
No.7, the 16 inch well rounded erratic, which was on the wall, and was given a possible Scottish source is still there. This is the most
important erratic in determining the source of the clays and erratics.
Erratic No.6 may be also by the farm entrance, the size is
similar to the quoted size (40 x 30 x 25 inches) and it is “a dark
grey, finely crystalline rock” .
If it is the same erratic it has been rotated so it doesn’t
match Taylor’s photo exactly.
The other two roadside erratics are much smaller and are conglomerates, one looks very like a sarsen type puddingstone. They don’t match any of the erratic descriptions.
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