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THE ESSEX NATURALIST
The Statistical Evidence for a
Conglomerate Alignment in Essex
BY E. A. RUDGE
EARLY IN 1949 our attention was drawn to a group of five boulders of
Hertfordshire Conglomerate, lying in an almost straight line two miles
long, at the western border of Epping Forest. The middle one of the
live was recorded by Salter, in 1912, in his List of Essex Boulders; and
is a well-known object, standing, 30 inches high, on a patch of river-
gravel at the hamlet of Holyfield (62/386080). The other boulders are
difficult to locate; two to the south-west are embedded in the soft soil of
the hill-side, and two to the north-east are concealed in the dense under-
growth on the woodland slopes leading to the plateau of Epping Upland.
Exhaustive search revealed only one other similar boulder within a
distance comparable with the average interval between the stones of this
series—at the gate to a pasture of Harold Park Farm, roughly 1,000 yards
north of the most easterly of the group.
The observed facts, therefore—five boulders of the same material, lying
in a short row leading from the Lea Valley to Epping Upland, in a
district remarkably free from puddingstone—suggested the possibility of
an extension of the series towards the east and west. The investigation
of this has been the object of an almost continuous field study over the
past four years, resulting in the discovery of the sites of close on two
hundred boulders, strung out in a straggling line through East Anglia,
Hertfordshire, Bucks, and along the Chilterns.
An account of our discoveries up to the autumn of 1951 has been given in
The Essex Naturalist (28, 172, and 29, 17), and it now appears desirable
to analyse the statistical evidence upon which we base our claim that
this long series is an alignment of related members. The discussion will
deal with two viewpoints—the random distribution of conglomerate in the
area covered, and the incidence of "pagan" stones in early churches.
The magnitude of the task involved has made it necessary to limit our
inquiry in the first instance to the County of Essex, but from cursory
observation it is probable that the findings reported herein apply equally
to the other counties traversed.
1. THE RANDOM DISTRIBUTION OF PUDDINGSTONE
It occurred to us, very early in this work, that the chief objection to
our claim that these stones formed an alignment would rest upon the
random distribution of these stones throughout the district. In other
words, our critics would suggest that we had merely drawn a continuous
line arbitrarily through the sites of such boulders as most conveniently
served our purpose. At all times, therefore, we have conducted a pains-
taking search for puddingstone boulders far beyond the region crossed by
our line. Since there is very little recorded information on the subject of
surface boulders in Essex, the task of plotting the positions of these stones
has been a personal one, involving a considerable amount of fieldwork.