SARSEN, BASALT AND OTHER BOULDERS IN ESSEX.
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road in the village of Arkesden are several large blocks of flint-con-
glomerate, and about half a mile distant on the road to Woodhall is a
large mass of the same material. This is not far distant from the Farn-
ham mass previously noted. About Clavering and Berden no boulders
were noted.
Cam Valley.—Just beyond the Essex border in a pit by the railway
at Hinxton, many sandstone boulders occur. In the pits near the railway
at Audley End a great variety of small boulders have been observed.
They include:—sandstones (various), quartz, basalt, fine grained pink
granite, rhyolite, pebbly-greywether, porphyry, Carboniferous sand-
stone, purple quartzite, etc. In the station yard is a fair-sized sandstone
boulder.
About half a mile from the station, at a spot near the top of the left-
hand slope of the valley of the Cam, is a large mass of calcrete, apparently
in situ. It is made up of flints, hard-chalk pebbles, grits, sandstones,
etc. By the main road from Audley End to Newport boulders of Neo-
comian and other varieties of sandstone are to be seen, and just before
entering Newport from the north is the large "Leper Stone" (7' x 6" x 1' 6")
composed of Neocomian sandstone (cf. Brit. Assoc. Report).
Saffron Walden.—Several boulders have been noted in this district.
Sarsens occur about two miles out on the Ashdon Road [s.]. Between Saffron
Walden and Little Walden, by the roadside, are boulders of basalt (decom-
posed), grit, sarsen, Neocomian and other sandstones. [c.]
Between Saffron Walden and St. Aylotts on the road to Ashdon,
the following boulders were observed :—Neocomian and other sandstones,
sarsens, Carboniferous limestone, two green igneous rocks, Jurassic
limestone, Septaria, Carboniferous sandstone, etc., Lying about the
Cement works on the Thaxted road are boulders of Carboniferous and
Jurassic limestone, purple sandstone, etc., probably derived from the
Boulder Clay pit at Seward's End, mentioned below. At the bottom
of the hill, leading from Seward's End to Saffron Walden, are three basalts,
the largest being 2' x 1'.
The section of Boulder Clay near Bean Hill, Seward's End, is interesting
from our present point of view. The largest boulders range up to 3',
but the average is from 18" to 20". They consist of :—Large flints, rounded
lumps of chalk, Carboniferous limestone, some being of a purple colour,
Jurassic limestone, Red Chalk (with belemnites). Kimeridge Clay, Jurassic
Septaria, Jurassic fossils, jasper, rhyolite (the only igneous rock seen).
The difference between these and the boulders found connected with
the clays on the higher ground is very noticeable.
Ashdon and Bartlow.—By the roads and in the farm yards in the
vicinity of these places the following boulders have been found :—basalt,
Neocomian sandstone, light grey limestone (Carboniferous ?), Jurassic
limestone, Lincolnshire limestone, Carboniferous sandstone with casts of
fossils. [s.]
South East Cambridgeshire.—Boulders similar to the foregoing are
found on the high ground at Balsham, Weston Colville, Willingham,
Brinkley, and Dullingham, and appear to connect the boulders of Hert-
fordshire and Essex with those of Norfolk and Suffolk. [s.]
Radwinter, Hempstead and Steeple Bumpstead.—Many basalt boulders
G