Pits and Ponds in Norfolk (Gruben und Teiche in der Grafschaft

10 Erdkunde Band XVI
war
eine komplizierte Natur mit sehr
er be
Aber
Eigenschaften.
widersprechenden
sie alle mit
seinem unbeugsamen
herrschte
zu erreichen, die sein
um die Ziele
Willen,
ihm gesteckt
ebenso
hatte.
groBer Ehrgeiz
?Ich habe meine Schiffe verbrannt und die Briicken
hinter mir abgebrochen. So verschwendetman keine
Zeit mit Ruckwartsblicken, denn man hat genug
Nansen
PITS AND
PONDS
Hugh
damit %u tun, nach vorwarts %u schauen." Diesem
er als Forschungsreisender
und
Prinzip folgte
dieses brachte ihm seinen friihen Ruhm. Spater
trat mehr und mehr die Pflicht in den Vorder
im Leben fiir sich selbst
grund, das bestmogliche
und damit fiir die anderen zu tun. Diese Haltung
beherrschte sein von alien bewundertes Rettungs
werk.
IN NORFOLK
C. Prince
With 7 Tables and 21 Figures
Zusammenfassung:
Gruben
und Teicbe
Norfolk
in der Graf schaf t
der Ordnance
Von den in der neuesten Ausgabe
Survey
27 015 Eintiefungen
sind die gro
Karten
eingetragenen
die auffallig
Umrifi
fien Steinbriiehe mit unregelmafiigem
sten. Sie kommen
in unregelmafiiger
in der gan
Verteilung
zusammen
zen Graf schaf t vor, machen
jedoch nur 1,5%
zu diesen verdankt
aus. Zusatzlich
eine un
der Gesamtzahl
der Ge
kleinerer Vertiefungen
Zahl
bestimmte
anderer,
ihre Ent
von Baumaterial
und Strafienschotter
winnung
haben jedoch
die meisten der Eintiefungen
stehung. Weitaus
im allgemeinen
oder
runden
einen
ellip
regelmafiigen,
in
assistance
for their valuable
of Geography
Department
1958 and spring
carried out in the summer
the field work
who
to the many
landowners
1959. I am indebted
kindly
to the
us to inspect their fields, and in particular,
allowed
and
Dr. W. O. Hassall,
his Librarian,
Earl of Leicester,
me
for permitting
F. S. Turner,
his Estate
Agent, Mr.
and other records at Holk
collection
to consult
the map
the
I owe
thanks for drawing
ham. To Mr.
J. Bryant
maps.
of
Among themost widerspread minor features
theNorfolk landscape are the small hollows which
tischenUmrifi und sind kleiner als ein acre (0,4 ha). Sie are to be found in almost
from
every field.Viewed
entsprechen den ?S6llen** (Sing. hSoII**) der Grundmoranen
a field theymay easily be
or
of
the
road
the
den
fol
edge
des nordlichen Mitteleuropa.
landschaften
(Vgl.
so
von C. Troll.)
Kessel
for ornamental
mistaken
Diese
sind oft in
clump plantations,
genden Aufsatz
der Mitte von Feldern gelegen und dicht mit Eschen, Eichen
well are they hidden by trees and shrubs. On closer
ortliche Bevolke
tiberwachsen. Die
und Hagedorngestriipp
of ash, oak,
inspection the dense undergrowth
des
Flurnamen
rung halt sie fiir ehemalige Mergelgruben.
hawthorn and elder is seen to form a ring sur
wahr
die Annahme
machen
14. Jahrhunderts
13. und
often occupied by
der Grafschaft
in vielen Teilen
ge
scheinlich, dafi damals
rounding a steep-sided hollow,
water. Seen from the air or
und eine erhebliche Zahl von Mergelgruben
a
clear
of
mergelt wurde,
deep,
pool
des 16. und 17. Jahrhunderts
sind auf Karten
eingetragen.
on a map they are sharply defined (Figs. 1 and 2).
von Giitern
beinhalten
Die
Eintragungen
Buchhaltungen
To describe briefly their form and pattern of
von
und Streuen unglaublicher
iiber das Ausheben
Mengen
Landwirt
distribution is the first object of this paper.
des 18. und 19. Jahrhunderts.
wahrend
Mergel
die er
die wichtige Rolle,
betonen
schaftliche Schriftsteller
Their mode of origin is not easy to discover.
in den Ge
von Schaf-Hutweiden
fiir die Urbarmachung
the variety of local topographic
By observing
Norfolk
im westlichen
bieten
leichter Boden
spielte. Am
such as slope, geology, soils and the
der
conditions,
Methode
kam
aber
diese
19.
des
Jahrhunderts
Ausgang
record of human activity within a particular area,
zum Erliegen
und wird
jetzt nirgends
Bodenverbesserung
simi
mehr angewendet.
alternative explanations formorphologically
von Norfolk
schei
der Eintiefungen
Eine gewisse Anzahl
be
lar hollows may
suggested. Then, by studying
zu
entstanden
des Bodens
nen jedoch nicht durch Ausheben
such as
of particular processes,
the operation
so seicht
so regelmafiig
im Umrifi,
sein. Sie sind entweder
dafi sie natiir
mineral working, marling, chemical weathering
annehmen mochte,
oder so grofi, dafi man
to
sind. Einige
an attempt may be made
davon,
and periglaciation,
Entstehung
licher, nicht anthropogener
wie die BrecklandMeere (Weiher)mogen als Erdfalle oder
in terms of related
hollows
explain particular
oder sehr kreide
des Kreidedurch Losung
?sink holes"
note that, apart from recent
entstanden
phenomena. We may
reichen Moranenuntergrundes
sein, andere, be
bear obvious marks of
few
mineral workings,
?thaw
im mittleren Norfolk,
sonders
mogen
periglaziale
von Boden
records indicate that a
sinks** (?Pingos**)
historical
sein, die durch Auftauen
yet
digging;
kamen. Wei
zustande
in feinkornigem Material
eislinsen
have
been dug in the past. It
of
number
pits
large
und durch Losung
entstanden
tere mogen
auf diese Weise
form is due to
feuchteren Verhalt
may be that some, whose present
unter kalteren
und
im Untergrund,
on
the sites of
been
have
man's
sein.
nissen als heute, vergrofiert worden
dug
activity,
as natural features.
which
originated
depressions
to University
are due
thanks
in Norfolk may be formed by several
My
Hollows
Acknowledgements:
a grant towards field-work
for
London
expenses
College
different natural processes but, in the absence of
several
who
to Mr. A. R. H. Baker,
and maps,
provided
of their formation, we
of
the
members
and other
F. C. Green
Mr.
directly observed evidence
photographs,
Hugh C. Prince: Pits and Ponds inNorfolk
11
Plantation
P/Cnngerhill
^
""""
' Extentof
photograph
Pond
Wood
* *| Scrub
Heath
23
860 yards
Fig.
Aerial
ref
view
of pits
125/788104
(Photo
and
looking
J. K.
S. St.
Fig. 2: Map
1:
ponds
near
north-east
Joseph,
Swaffham
towards
copyright
from Grid
Castle
Acre.
reserved)
than suggest which areas offer, or
formerly offered, favourable conditions for cer
to operate. As a basis for further
tain processes
discussion it seems appropriate to consider some
possible origins of pits, ponds and other enclosed
set
in relation to their geographical
depressions
an
to
is
is
exercise
What
present
attempted
ting.
inmap interpretation.
can do no more
The form and distribution ofpits and ponds inNorfolk
The current 1 : 25,000 Ordnance
Survey maps
mark 27,015 hollows of different shapes and sizes
or other water-filled hollows,
(Fig. 3). Ponds
coloured blue on the Ordnance map, are distin
from dry pits, indicated by hachures.
guished
Most pits and ponds are situated in areas where
the cover of glacial drift is more than three feet
thick (Fig. 4). If the areas of thin drift deposits in
west Norfolk be included, the correspondence
of pits and ponds
shown
on Fig.
1.
between areas of hollows and glacial drifts is
these limits the density
almost exact1). Within
of hollows varies considerably, and appears to
differ from one soil region to another (Fig. 5)2).
The number of pits and ponds and their density
x) In discussing the drift deposits of Norfolk I have
the terminology
D. F.W.:
followed
Baden-Powell,
and interpretations
proposed
The Chalky
Boulder
Clays
Norfolk and Suffolk. Geological Magazine
in
of
85, 1948,
and Adjoining
C. P.: East Anglia
279?296;
Chatwin,
British Regional
Areas.
Survey. 2nd
Geology.
Geological
R. G.
and Donner,
edit. London
1954; West,
J.J.: The
and the East Midlands.
Glaciations
of East Anglia
Quart.
R. G.:
The
Soc.
West,
112, 1956, 69?91;
Journ. Geol.
in East Anglia.
Pleistocene
3,
Journ. Glaciology
Epoch
1958, 211?216. Fig. 4 is based on theGeological Survey
Quarter-Inch
Drift
Geology
Sheets
12 and
16.
2) The regional divisions (Fig. 5) have been drawn with
the aid of Arthur Young's Map of the Soil of Norfolk.
of the County of Norfolk.
General
View
of the Agriculture
London
map of the regions of
1804, and J. E. G. Mosby's
193.
of Britain.
Norfolk.
London
Land
Norfolk.
1938,
are described
in Newman,
L. F.:
The
Soils of Norfolk
of the
Transactions
Soils
and Agriculture
of Norfolk.
Naturalists'
and Norwich
Norfolk
9,
1914,
Society
F.:
Soil
H. H.
and Hanley,
and Nicholson,
349?393;
in East Anglia.
Book
for the Excursion
Guide
Conditions
Soil
of
International
Britain.
Third
round
Congress
Science.
Oxford
1935,
60?74.
12 Erdkunde Band XVI
Table I: Pits and Ponds inNorfolk
Surface
Number
of
Area
Dry
Region
sq. mis.
Fenland
Pits
Number
Ponds
3
Number
ofWet
212
of Pits
&
Density
Density
Pits
Ponds
of Dry
Ponds
518
521
123192
1244
1436
1.5
10.1 11.6
2484
1701
4185
6.4
4.3 10.7
1125
224
754
1879
5.0
3.4 8.4
391
932
8616
9548
2.422.0
South Norfolk
279
600
6790
7390
2.124.3
Loam Region
339
645
1340
1985
1.9
3.9 5.8
Greensand Region
Good Sand Region
Breckland
Mid-Norfolk
389
97 4328
Broadland
Total Norfolk
2054
6009
21006
have been calculated for each region (Table I). In
areas of light soils, particularly in the Good
Sand
are
the
hollows
occasion
generally large,
Region,
not as numer
ally more than 100 feet across, but
ous as in areas of heavy soils in mid-Norfolk
and south Norfolk, where small pits and ponds
In the densely pitted central districts,
abound.
where blue chalky boulder clay of the Lowestoft
thickness and the level
till attains a considerable
of ground water is high, most hollows are perma
nently water-filled. In the Fenland and Broadland
there are notably fewer than elsewhere, for they
are, in fact, absent in areas of deep peat and recent
of Pits
&
Ponds
2.4 2.4
0.01
71
Density
ofWet
24.4
26.4
0.30.4 0.7
2.910.2
27015
13.1
in the Fakenham
district are somewhat
in mid-Norfolk. To
than
those
and
deeper
larger
find what kind of material lies at the bottom of
the hollows is far from simple. They are thickly
downwashed,
overgrown,
partly filled with
hollows
Table
II:
and
Shape
size of pits
in the Fakenham
and
ponds
district
Surface
Shape
Area
alluvium.
the summer of 1958 an attempt was
During
made to record the shape and size of the hollows
on the
or
pond marked
by visiting each pit
six-inch map, Sheet 25, covering 24 square miles
in north-west Norfolk (Fig. 6).
around Fakenham
To compare the hollows in an area of light sandy
district with those in an
soils in the Fakenham
area of heavy soils in mid-Norfolk,
another 6
square miles around Seaming was surveyed in the
are circular, elliptical
spring of 1959. The hollows
or irregular in shape, except where two or three
occur together at the same site as multiple hollows
are less than 300 feet
(Table II). The great majority
across and few are more than 30 feet deep. The
3
-3 *
u
Gravel pits
Other pits
on arable
26
w
0
4
a
17
?
*
2
2
j
5 43500 ?
?
.fr
s
468 139 215 28
86
74 30
9
8
3600 6300 1500
land
Other
pits
on nonarable
Total
150
37
land
644 176 293
75
100
1200 3600
300
Hugh C. Prince: Pits and Ponds inNorfolk
(more
BZ?2z2(less
the
^
"
^
than
3ft.
surface)
below
'-1
/
IIlcha,k
"^^^-'^
13
/==
Ten mi/es
J
4: Glacial drift inNorfolk. Based on Geological Survey XU"Drift Geology Sheets 12 and 16.
JFig.
weathered debris, and often contain a considerable
of them have not been
depth of water. Most
disturbed
for a long time. In the Fakenham
district 619 of the hollows recorded on the six-inch
map of 1904 can still be identified; and of those
that have disappeared
five have been filled in as
refuse tips.With the exception of six recent gravel
have
only four other new hollows
workings,
appeared since 1904. The evidence of the six-inch
shows that they cannot be
map
convincingly
as
craters or other twentieth
bomb
explained
century phenomena.
Mineral
workings
Of the pits and ponds shown on 1:25,000 maps,
404 are named and distinctively represented as
chalk pits, lime kilns, gravel pits, sand pits or
brick kilns. The map (Fig. 7) shows that, apart
from the Fenland and Broadland, mineral work
is almost ubiquitous.
Its limits
ing in Norfolk
correspond closely with the limits of all types of
hollows, but, unlike other hollows, quarries are
not concentrated in south and mid-Norfolk. The*
map also shows remarkably little differentiation
in theworking of differentmaterials. Sand, gravel
and brick pits are situated in every part of the
county except in the Fens3) and the Broads. Chalk
pits and lime kilns extend from the western edge
of the chalk outcrop as far east as Southrepps near
on the
Neatishead
Mundesley,
edge of Barton
Broad and Whitlingham
cliffs below Norwich.
Some deep pits such as those at Thorpe produce
sand, gravel, clay and chalk at different levels, and
adjoining pits at several places in mid-Norfolk,
south Norfolk,
the Good
the
Sand Region,
Breckland and the Greensand
Belt produce diffe
are now
rent materials. A variety of materials
being extracted from all districts where hollows
occur, and it is pertinent to ask whether other
hollows, not named on maps, are the result of
mineral working.
Pits at present in use are not difficult to recog
nize (Fig. 8). Most are dry or well drained. Those
excavators are irregu
being dug with mechanical
at Terrington
3) A brick works
on current maps.
fen is marked
St. Clement
in the silt
'^X^?-^^^^^^^^^^^^
&
)
^
vV;::::Nr:;::|
^
<or\^*^X/
T
I'^'iy/SS
^
^""'^^^
FTTH Alluvium,Peat
-l and Fen
K:
-1
>f
^
'
j EastDereham!
Kl ~
D c r>
norfolk
\
^^^^
I/'Thetford'
&
Vk^%^^^-^?.\
Silts
^^^^^
r e g io
/
/<V;:^^^^W
j-.::y::':y-.:yf
loam
FakenhaTn^
\\
i v
f=
f
^-'^
norwich
south
no r fo l
>^
n^^^^^l
;C
^^^&.
/P \
broari^and^
J-.-^^fE
"^^s
k^@^^
p
J
"
/
^~"~^^_N^'/
/=
Tenmiles I
I_M
Fig. 5: Soil regionsofNorfolk. Based on maps of ArthurYoung
lar in shape and occupy large areas, the largest
more than 100 acres. They are situated either at
the side of public roads or are served by tracks.
Fresh exposures of material quarried, or derelict
remains of tramways, graders, sheds and kilns
evidence of recently aban
provide unmistakable
a very
doned workings. Modern
diggings present
from the great majority of
different appearance
situated in the
small, regularly shaped hollows
middle of fields (Fig. 9).
account
for
day mineral workings
all
of
and
but
barely 1.5%
pits
ponds,
archaeology
and historical records enable us to identify pits
which were
formerly dug for flints, building
materials and road stone. Many were very small
in the
The
earliest diggings
scale workings.
Breckland may be traced at least as far back as
Neolithic
times4). Until the end of the nineteenth
from pits at
century gunflints were obtained
as well as from the
Catton and Whitlingham
in the
Brandon district5). Subterranean workings
chalk near Norwich at St. Giles Gate, Stone Hills
Present
R. R.: East Anglia.
London
1960, 51?58.
4) Clarke,
of Gun
the Manufacture
S. B. J.: On
5) Skertchly,
Geol.
Flints. Mem.
1879, 10, 14.
Survey. London
(1804) and J. E. G. Mosby (1938).
on the Dereham
road, Catton and Whitlingham
probably provided much of the chalk and fresh
jflintsused in themedieval buildings ofNorwich6).
stone has also been obtained from the
Building
Lower Greensand,
and since the thirteenth cen
tury from the hard beds in the Lower Chalk in
west Norfolk7).
By the seventeenth century al
most every village had its small pits for supplying
and material
for brick
gravel for road making
noted that many of the
making. W. G. Clarke
small disused pits, which are one of.the most
characteristic features of commons and village
existed at the time of enclo
greens in Norfolk,
are
not
reached by present day
Others
sure8).
metalled
roads. A survey of 1779 records hun
6) Woodward,
Norwich.
around
129?130.
28?30,
H. B.:
Mem.
The Geology
Geol.
Survey.
of the Country
London
1881,
in the
walls
of Marham
founded
nunnery,
7) The
built of clunch
thirteenth century, were
almost
certainly
from the neighbouring
F.: An
derived
pits. Blomefield,
a Topographical
of the County
of
towards
Essay
History
London
1807.
Vol. VII
Norfolk.
Parkin).
(by Charles
392.
8) Clarke,
actions Norf.
The
W. G.:
Nat.
Norw.
of Norfolk.
Commons
Soc. 9, 1910, 52?70.
Trans
Fig.
Pits
6:
the
district
in
ponds
Fakenham
f
and
showing
ield
their
relation
boundaries.
to
and
roads
Based
field
on
survey
in
August
1958.
?
0>
Pits
Gravel
4*
Other
pits
ponds
and
mile
one
16 Erdkunde Band XVI
+
"j^FTT3?-;
/f*
+
I
I a+o+++
/
oo
? *
- fo
\
+
+
V
^T^^3^
/
VXo
o?o0
o0O
+o0o
->a\SS?
OA
+o
W
ty
I
u
0 j,
+
O
o
?
O
a?
a
+
+
?
o
o
o
o
?
a
o
A
+A
+^ + + +
-
+
Chalk and Lime a
Gravel and Sand
Brick-kiln /
7"e/?mi/es
/
a
oo
?
a
?
a
a
A+
a
H
X
a
^a
?+
a a
a
XZZZZZZZZZZZZ
.
XX
a
a
o
aa
o\
a
?
a
+
?
8q?a
\
? ?
a
- -
=
?+o
\
\
V=
Ao
?
A ??o
a0
: f r?A?
a
?a
o?
?^ 4
F
+A A
oo ++o
o
^
b
J?
/
r
\
0
a ^y^^/
fc= ^
^A
* EE
?^
^
=
+aa?a^>oA
o
a
*
.i? .
Xa
a
o
o
^
?a
? o
?
\-~?Q
a
a+
A ooOo
/ ?o? oa
+o
+
o
+ aoa
OA
a aV
+X -
a
r +o
>^
?
? Vjf
>y
X_
+
a
o
J o
(
)
aa+?a?+
a
+
+o \
+
\
0??
+
a
aa
??H
+
o
?o
N
0
a
o.
1
oo
o >w o
\=
V
/=
?
a
/ ^y
~
.Fig. 7; Mineral
Based on Ordnance
workings
Survey
dreds of such pits in different parts of the Holk
ham estate. It shows two small brick kilns and a
lime kiln in the outlying parts of Great Massing
ham, two gravel pits and a chalk pit inWeasen
ham, and at least two gravel pits and a sand pit in
Castle Acre9).
are much less
Many disused mineral workings
than one acre in extent and cannot be distinguish
ed from other hollows. A few can be recognized
traces of
by their somewhat irregular shape and
tracks leading to them. Gravel and sand pits may
be colonized by bracken, gorse, birch, oak and
hawthorn, but rarely by ash (Fig. 10).
Ponds and Pits
The great majority of hollows in Norfolk are
much smaller than one acre in extent and much
modern mineral
more
regular in shape than
hollows may be
such
In
clay country
workings.
1779 survey is contained
9) The
Estate
plans kept in the Holkham
in a bound
Office.
volume
of
in Norfolk.
1 :25.000 maps.
expected to collect water from ditches and field
drains, and some may have been dug expressly for
this purpose. But in sandy districts, where the soil
is naturally well drained and artificial drainage is
absent, there are some 10,000 hollows, half of
them filled to within a few feet of the surface with
water.
Some, which are very shallow and lie
within or close to farmyards or in fields of perma
nent grass, are ponds used, or formerly used, for
such as the
stock. Some large ponds,
watering
as
Brooke meres, may have been excavated
reservoirs for water for cattle or even for the
human population10). But more than 70% of the
district are
in the Fakenham
pits and ponds
situated in arable fields, about half of them in the
middle of fields, away from roads or farm build
near Faken
ings. A farmer in Great Ryburgh
ham has at least one pit in 20 of his 24 arable
fields, one hole being over 80 feet deep. These are
nor
ponds.
evidently neither drainage sumps
10) Woodward,
Norfolk.
History.
H.
Vol.
B.:
Geology.
I. Westminster
Victoria
20.
1901,
County
Hugh C. Prince: Pits and Ponds inNorfolk
\ * .Q\\?
r-^/V
17
\ ^~?\
\B e *a
\\ W
\/
c o\\n
abandoned
sand and gravel pit at Hempton.
Fig. 8: Recently
Green
south of Fakenham,
Grid
ref. 125/911286.
(Photo A. R. H. Baker)
The modern farmer regards them as a nuisance.
in the 24
space;
They occupy much valuable
around
Fakenham
square miles
they occupy
127 acres, or 0.8% of the surface area (Table III).
Table III: Area ocupied by pits and ponds in the
Fakenham
district11)
Pits and Ponds
Surface_._._
Acres
j^ble
kncT
Total
Area
a
cres
Percf"?f
surface
Number
Per cent
10752 66.9
0.62
471
73.1
4608 59'8
1,29
173
26,9
0.82
644
15360 126.7
Pond
area
100.0
?3P
_440
Fig. 9: The
I? IWood
WPit
EZ1 Scrub
I.I Heath
Gravel pit
contrast
between
yards_
small
regularly
shaped
hollows
in themiddle of fields at Beacon Hill and large irregular
at Hempton
Green near Fakenham.
gravel workings
on field survey in August
Based
1958.
is hindered by their
operation of machinery
presence in themiddle of fields, and as a result it is
to plough
impossible
straight furrows or drill
straight rows. The cover of trees casts its shade on
land and harbours multitudes
of
surrounding
are
and
rabbits.
vermin,
pests
notably
Crops
stunted or severely depleted in an area which may
extend ten or fifteen feet beyond the edge of a
hollow. On the other hand, the task of filling
The
total area occupied
represents
lr) The
by pits and ponds
the sum of the areas of 644 ellipses whose
lengths and
on the ground
breadths
have been estimated
and checked
the six-inch map.
The
of arable
land
proportion
against
the total area of hollows
represents
by hollows
occupied
or growing
in fields that were
in
arable crops
ploughed
as a percentage
of the total area
1958, expressed
August,
on the current Ordnance
of those fields shown
Survey
acres of arable
includes
land
10,752
1:2,500
plans. The
occupied by hedges, ditched, footpaths, bridleways and
also
by pits and ponds
themselves.
Fig.
10: Old
disused
gravel
pit
elder at Hempton
Green
A.
R.
H.
(Photo
covered with
near Fakenham.
Baker)
gorse
and
18 Erdkunde Band XVI
them is expensive and has not always proved
successful. The thicket of trees and shrubs has
first to be cleared;
then several hundred cubic
to be found and carried
of
material
have
yards
across fields. When
this is done, a wet patch may
a normal crop
remain incapable of producing
(Fig. 11).
have a vertical shaft penetrating to a depth of at
least ten feet (Fig. 13). Ash, hawthorn and oak are
the commonest
trees, but elder, willow, black
thorn, holly, alder, elm, sycamore, hazel and
Scots pine are also frequently present (Fig. 14).
Trees of all ages from young saplings to mature
are found on the sides of many
specimens
pits,
Fig. 11: Wet patch remainingafter a pit had been filled in
near Colkirk.
3rd August
taken on
Photograph
period of drought.
Fig.
12: Pit
(Photo
1958 after a prolonged
A. R. H. Baker)
on
side of a hill covered with
and oak near Raynham
Park.
Grid ref. 125/884276.
Marl
Fig.
ashy hawthorn
pits and marling
In areas of flat arable land pits and ponds are
regularly spaced in each field, except where two or
three occur side by side as multiple hollows; on
sloping ground they are generally situated near
the highest point in a field. Some, cut into the side
of a hill, are approached by a gentle incline which
may look like a natural depression, backed by a
steep face ten or twenty feet high (Fig. 12).
Others, whose presence on a level surface is often
revealed by a dense thicket of trees and shrubs,
Fig.
13: Pit on level ground covered with
near Great Ryhurgh.
hawthorn
(Photo A. R. H. Baker)
74: Pit
Grid
on
level stony ground
and elder neat Pudding
ref. 125/935281.
(Photo
ash and
Scots
supporting
Norton.
A. R. H. Baker)
pine
showing how little they have been disturbed in
recent times. Yet the reports of
people now living
and the records of marling activity up to the end
of the nineteenth century suggest thatmany were
dug formineral manures.
For the present purpose the term "marling"
is
used to refer to the digging of any mineral sub
stances from beneath the surface soil to correct
soil acidity or to improve soil texture. Geologists
define marl as a calcareous clay containing more
than 10% calcium carbonate, but inNorfolk
the
term "marl" is generally reserved for soft white
materials
containing a very high proportion of
Hugh C. Prince: Pits and Ponds inNorfolk
calcium carbonate. Joshua Trimmer applied the
term exclusively to almost pure calcium carbonate
obtained from the Upper Chalk, transported or
disturbed masses of chalk, or the intensely chalky
In mid
boulder clay of north-west Norfolk12).
Norfolk and south Norfolk sandy substances rich
in lime are also called "marl". The term "clay" is
a lower lime
applied to other substances with
In
its
local
meaning, "clay" includes
content13).
or
blue
till, some of which
chalky
grey,
yellow
contains more than 80% calcium carbonate and is
pure enough to be burnt for lime14). It also
includes sandy loam, as well as true clay from the
formations. The value of
Gault and Kimmeridge
all these materials,
except the true clays, for
soils
be attributed largely to
may
improving light
their lime content. On the light sandy soils in
west Norfolk "clay" or "marl" is used to reduce
acidity, to increase thewater-retaining capacity, to
retard the leaching of plant nutrients from the
topsoil and to prevent soil erosion. On heavy soils
the "marl" of south
sandy calcareous material,
to
can
used
be
Norfolk,
improve soil texture. The
sand fraction helps to break down stiff,tenacious
clods by a mechanical
process; while the lime
fraction not only reduces acidity, but also imparts
an easily worked crumb structure by a chemical
process of flocculating the clay colloids. At least
eleven different substances were used to improve
in the mid
different types of land in Norfolk
nineteenth century but the method of obtaining
them was much the same in all districts.
The digging of mineral manures was practised
over two thousand years ago. Pliny
in England
raised by
such material was
how
described
windlass from depths of as much as 100 feet. This
method of sinking a deep shaft and excavating a
bell shaped cavity below is described by many
later observers and has been reported in the
present century by several authorities15). On a
as
of Norfolk
On
the Geology
Joshua:
12) Trimmer,
of soils. Journ. Roy.
illustrating the laws of the distribution
Soc. 7, 1847, 444?485.
Agric.
these terms have different mean
13) In other counties
as "marl" would
in west Norfolk
is described
ings. What
in Hertfordshire;
be called "chalk"
while much
probably
as
in Norfolk
be described
would
of what
is called "clay"
or Kent.
in Hertfordshire
"marl"
of the Country
H. B.: The Geology
14) Woodward,
Mem.
Surv.
Geol.
Wells
and Holt.
around
Fakenham,
London
1884, 23, reports that chalky boulder
clay in a pit
near Holt was
calcium
found to contain
carbonate,
91%
as to be readily
a material
so free from other detritus
mistaken
for pure chalk.
of the Soil. London
Sir E. John: The World
15) Russel,
a passage
from Pliny's
Natural
1957, 172, quotes
History
from bell pits in
of extracting marl
the method
describing
two
Russell
the
observed
Britain
thousand
years ago.
same method
at
of itinerant workmen
used by a gang
in 1915. The
of agricultural
Rothamsted
observations
are reviewed
on this subject
G. E.:
writers
by Fussell,
19
was occasionally
sloping surface it
possible to cut
to reach the
back into the slope far enough
material by way of an inclined ramp and draw it
out in carts with the aid of a capstan16). The first
method would account for the depth and funnel
shape of pits on level surfaces; the second would
explain thewedge shape of the few pits on sloping
surfaces. Raising material
from a deep vertical
shaft is a laborious operation, but less costly than
opening a broad pit. The cost of digging and
loading the material into carts is often no greater
than the cost of carting and spreading it with
or cumbrous carts. To carry it the
wheelbarrows
shortest distance, a pit should be situated in the
middle of a field or at the top of a slope, so that
loaded carts may run downhill. A further advan
tage of digging a shaft is that a minimum quantity
of "uncallow"
overburden
needs
removing.
The "uncallow"
is generally spread on the land
with the "callow" marl and not thrown back into
ten or
the pit after themarl has been taken. When
more feet of overburden has to be removed to
reach a productive bed, a vertical shaft is most
appropriate. The shape, size and position ofmany
present day pits correspond faithfully with these
specifications.
The earliest documentary evidence of marling
in Norfolk
is derived from medieval field-names
and minor place-names which indicate the pres
ence of marled land, marl
pits, clay pits, loam pits
or pit holes. One of the earliest references is a grant
at
of five acres of land, called Marlepitlond,
in
north-east
in
made
Norfolk
Saxthorpe
127717).
In the sandy districts of west Norfolk
the ferti
lizing value of white chalk marl was known and
widely exploited in the thirteenth, fourteenth and
states that "land
fifteenth century. W. G. Clarke
which is now apparently primitive heathland was
profitably cultivated" at that time18).Among other
places he identifies the present Lambpit Hill
in Thetford Warren as the Lampythowe
referred
to in 1338, in which the element "lam" means
"loam". Another pit near Thetford is referred to
in 1535 as Fryers Calkepitt. Place-names
contain
ing the element "cork", as in the present Cork
mere Bottom, Wretham,
or Corkes Pitte, on the
an ancient manure.
Nature
One
Marl,
183, 1959, 214?7.
of the best twentieth
is by Sherlock,
century accounts
R. L.: The Geology
of the Country
around Aylesbury
and
Hemel
Mem.
Geol.
1922, 55.
Hempstead.
Survey. London
Arthur:
of Agriculture.
19. Bury
Annals
16) Young,
St. Edmunds
1793, 478.
on the Mss.
of the
Mss.
Comm.:
17) Historical
Report
at Blickling
of Lothian
London
Hall, Norfolk.
Marquess
1905, 50. The marlpit is also referredto in a grant of 1252
cited on p. 48.
W. G.:
18) Clarke,
revised
and re-written
1937, 97.
Cambridge
In Breckland
Wilds.
by R. Rainbird-Clarke:
2nd.
edit,
Heffer,
20 Erdkunde Band XVI
map of theManor of Farnworth Hall in
Ashill, 1581, probably refer to the hard chalk of
that name described by Arthur Young19). Many
hundreds of early forms of place-names have yet
to be studied before a geography of marling
in
medieval Norfolk can be written, but it is evident
from the earliest farm and estate maps that marl
feature of the landscape of
pits were a widespread
north-west Norfolk by 1600.
Holkham
and probably several others25). Marling
Holkham
was usually paid for by the tenant himself, except
when new land was being enclosed and improved.
Books
The Audit Account
of the Holkham
Estate, which begin in 1707, record only the
payments made by the landlord as a contribution
to the initial cost of reclamation;
the tenant, for
his part, generally agreed to pay an increased
rent26). A typical entry in the Audit Account,
under "Holkham,
1712", referring to such an
A remarkable collection of maps and plans of
reads:
estate dating back to 1575 show
the Holkham
agreement,
"Allowed Thos Magnus for filling and spreading
many marl pits and clay pits20). Most were located
500 load ofmarie laid upon 10 acres inHigh Close as
in minutely subdivided fields and small closes of
two or three acres immediately surrounding villag
by agreementwhen he took thefarme which was part of
es and hamlets, and itwould seem that before 1660
the considerationof his increase of rent...
? 7.10. Od"
most marling in north-west Norfolk on lands that
with
together
hedge planting and the
Marling,
were regularly under cultivation. It is not certain
carried out on newly
building of farms, was
how extensive the practice was at this period in
estate
enclosed land in every part of theHolkham
the rest of the county, particularly in the old
the
first
of
the
half
century
during
eighteenth
enclosed districts of mid-Norfolk,
although it is
(Fig. 15). By 1750 marling on a large scale had
not
an
was
innovation of the early
clear it
come to be regarded as an essential step in the
entirely
reclamation of land from sheepwalks27). To more
eighteenth century. In east Norfolk chalk shipped
in Kent
from Greenwich,
Erith and Northfleet
than one writer marling was the cornerstone of
was carried as much as ten or fifteenmiles inland
in west Norfolk
hus
the improvements made
it was
from the ports, where Defoe
observed
bandry during the early eighteenth century. One
to
asserted that "all the countryfrom Holkham
eagerly sought by farmers "to lay upon their land,
and that in prodigious quantities" 2iV).Although
a
was
the
wild
spirit of
Houghton
sheepwalk before
this trade may have contributed to the fertility of
improvement seized the inhabitants.What has wrought
it is unlikely
the coastal fringe of east Norfolk,
these vast improvements is themarling; for under the
that imported chalk was used outside the Loam
whole countryrun veins of a very rich soapy kind, which
In other parts of the county marl was
Region.
theydig up and spread upon the old sheepwalks; and
was used.
it
field
in
in
the
which
generally dug
then, bymeans of inclosure, they throw theirfarms into
a regular course
After 1660 it is evident that marling was
of crops, and gain immensely by the
an oversimplification
to say
improvement"2*). It is
extensively practised on lands newly won from
occurs
the
in
under
veins
whole
that
marl
It
from
and
from
county,
"breaks",
heaths22).
sheepwalks
but the effect of its application on many types of
came to play a leading role in the reclamation of
on the
land was spectacular. "The fertility of this land is
light sandy soils in west Norfolk, notably
estates
of
Houghton24),
Raynham23),
great
19) Young,
St. Edmunds
20) They
Arthur:
Annals
1803, 172.
show, for example,
of Agriculture
that there were
39.
no
list of the Cholmondeley (Houghton) MSS.
Bury
less than
28 pits inTittleshall in 1596, 10 inLongham in 1580 and
in 1575.
Lexham
A Tour
and
Daniel:
through
England
21) Defoe,
1927. Vol.
London
Wales
I, 99.
(1724). Everyman.
are temporarily
or "brecks"
"brakes"
22) "Breaks",
or heaths, which
from sheepwalks
enclosures
cultivated
to revert to
are cropped
for a year or two, then allowed
are described
in Saltmarsh,
John,
They
rough grazing.
a Nor
H. C.: The Infield-Outfield
und Darby,
System on
and Mosby,
30?44
Hist.
Econ.
folk Manor.
3, 1935.
4 inWest
cit. 127?131.
J. E. G.:op.
at Rainham
Estate Management
H.W.:
23) Saunders,
and 1706. Norfolk
1661?1686
in the Years
Archaeology
on the Rayn
that marling
shows
began
19, 1917. 39?66
earlier than suggested
ham Estate
before
by
1664, much
Past and
R. E. (Lord Ernie), English
Farming
Prothero,
Present. London
1912, 174.
and Norfolk
Sir Robert
Walpole
24) Plumb,
J. H.:
2nd. Ser. 5, 1952. 86?89,
Hist.
Rev.
Econ.
Husbandry,
G. A.: A Hand
refers to marling
1701, p. 87. Chinnery,
Cambridge
the General
Estate
under
lists marl
Accounts,
3 vols.
1718?1745,
in
Norfolk.
Gentle
Tne
state of Husbandry
25) ?N?.
of Lyng
man's Magazine
22, 1752. 453, credits Mr. Allen
of Dereham,
with
north-east
House,
initiating
large-scale
as a means
in west Nor
heathland
of reclaiming
marling
Arthur:
op. cit. 1804. 365, adds the names
folk; Young,
to the list of pioneer
and Mr. Morley
of Lord Townshend
1953.
improvers.
26) The
in Parker,
nature of these agreements
is discussed,
p. 165
and the Agrarian
of Norfolk
R. A. C.: Coke
Econ. Hist. Rev. 2nd. Ser. 8, 1955. 156?166.
Revolution,
to
on the demesne
lands was
charged
normally
Marling
to in Rogers,
A
referred
the Farm Account,
J. E.T.:
in England,
Prices
and
of Agriculture
vii,
History
Part I. Oxford
1703?1793.
1902, 646.
soils
reclamation
of
in
the
role of marling
light
27) The
at length
the early eighteenth
century is discussed
during
in Nor
Revolution
The Agricultural
Naomi:
in Riches,
Hill
of North
folk. University
1937,
Carolina,
Chapel
152.
33, 77?81,
28) A Society of Gentlemen
P., and Price,
by Russell,
:England
Revised
Displayed.
London
1769. i, 318.
Owen.
C. Prince:
Hugh
Pits and Ponds
1729-30
^.Queries
+
\
-
Dunton
Flitcham 1735-45
\S
1726-8
Southcreake
1734-5 "X
1
+
\
+
inNorfolk
21
^>Ny
>y
Fulmodeston
1712-50 X
I
Massinghaml708-I4
+
>.
\
,Wellinghaml738-9
_Q.?.
Mn
^ _ .-^
yWeasenham 1738-50/ +
\
+ B.?..ngford .726-42
1742-50
V=?
Tittles^
^Xr^^^N^-^1
Castle Acre
1735-53
\
\
-?k'
Holkham Audit Account
Dates
refer to entries
Books f
Ten miles
Based
in
FE
-^^^^^^-^
V_^-s_h
_^ f
>
j
i
f^
/
on the Holkham
Fig. 15: Marling
on Holkham
Audit Account
Books
record
de la
wholly artificial", declared the young Due
after visiting a prosperous farm
Rochefoucauld
atDunton
in 178429). In the course of his visit he
learned that this and many other farms in the
district had been uncultivated waste fifty years
earlier and owed their high state of cultivation "to
the discovery ofmarl". On estate maps of the mid
eighteenth century pits appear frequently in the
midst of "breaks". In the 1750's a pit ismarked in
Marl Break inGreat Massingham;
in 1779 there is
a New Marl'd Break in
and a Claypit
Rougham
Break in Tittleshall, to name but three
examples
from maps of the Holkham
estate.
While newly reclaimed intakes inwest Norfolk
were being marled
possibly for the first time, the
activity was being revived in the old enclosed
lands in east Norfolk. William
who
Marshall,
acquired a knowledge of the practice from two
in England
29) Ed. Marchand,
Jean: A Frenchman
sur l'Angleterre
of Francois
de la
1784, being Melanges
Rochefoucauld.
with notes by Roberts,
Translated
S. C.
on marling
other
observations
1933,
230;
Cambridge
on
appear
p. 172?173,
217, 218?219.
estate
between
payments
1712
and
for the initial
1756.
improvement
of land.
in east Norfolk
residence
years'
(1780-1782),
made a careful study of the properties and mode
of the marls
of occurrence
and clays used
in different parts of the county30).
Samples
on the
of chalk marl
from Thorpe
Market
northern edge of the Loam
region, clay marl
in East Flegg,
from Hemsby
soft chalk from
and
hard
chalk
from
Thorpe-next-Norwich,
Swaffham on the borders of the Breckland and the
Good
Sand Region were analysed and all were
found to contain a high proportion of calcium
carbonate. But their usefulness also depended on
the rate at which theyweathered and mixed with
the soil; and on the nature of the soil itself. It was
recognised locally that the presence of buddle or
corn
(Chrysanthemum segetum), smart
marigold
weed
(Polygonum Hydropiper),
quick or couch
grass (Agropyron repens) indicated that the land
needed marling.
It was also observed
that the
30) Marshall,
William
:The
Rural
Economy
of Nor
folk.London 1788. i, 16, 18?27, 150?157, 217; ii, 193,
363?364.
22 Erdkunde Band XVI
1804
-
^
s?
r''s
111
. Pm
'i
1844
?^_
e???
of the county was justly famous had been achieved
by the institution of 21-year leases, by the enlarge
ment of farms, by the enclosing of heathland, by
strict adherence to regular rotations of crops and
by marling, which he claimed to be "the most
important branch of Norfolk
improvements"^).
In 1804 marling or claying was practised on a
large scale in most parts of the county (Fig. 16),
but the quantities used were no longer as great as
in 1771, at the time of Arthur YoungV
Tour33).
was beginning
to demonstrate
the
Experience
In
the
smaller
of
country
advantages
dressings.
between Warham and Holt where itwas customary
to spread 60 loads34) per acre in 1771, good results
were obtained with 25 to 30 loads in 1804; and
that received 70 loads per
land in Massingham
acre in the 1770's derived no less benefit from
35 to 40 loads per acre 25 years later35). But there
were still great differences between the amounts
used in different localities. Much
larger quantities
were applied inwest Norfolk than in the east. In
the west dressings of "clay" ranged from 40 to
140 loads per acre; in the Loam Region dressings
were not more than 40 loads per acre, and the
east Norfolk
widely dug white chalk "marl" of
was generally spread at a rate of 8 to 12 loads per
acre.
we
appreciate the scale of these operations
at
a
the
field
that
reckon
may
clayed
forty-acre
rate of 60 loads per acre, which was quite typical
forwest Norfolk, required 2,400 loads, or about
this
3,200 cubic yards of material. To provide
a hole 60 feet in diameter and over 30
quantity,
feet deep would have to be dug; for a ten-acre
field a hole 30 feet across and over 30 feet deep
be required. Similar diggings might be
would
at intervals of twenty or thirty years,
repeated
or near the site of the original pit.
at
usually
confirm that the pits are roughly
Observations
to the size of fields, that their
proportional
the
very roughly with
corresponds
capacity
and that
amounts reported by Arthur
Young,
multiple hollows could have been produced by
To
6
^^V^~7oo^L^x>
^
w-^?,_^
I
of marl
Fig. 16: Quantities
spread in Norfolk.
to the number of loads of marl
circles are proportional
Young
from Arthur
derived
spread per acre. Information
(1844) and other accounts.
(1771 and 1804) and R.N.Bacon
The
or
disease "anbury" or "clubroot"
"flnger-and
toe" (Caused
by the organism Plasmodiophora
brassicae) in turnips and members of the cabbage
occur on recently marled land31).
family did not
On the other hand, it was noted that coltsfoot
thrived where marl lay close to
(Tussilago Farfara)
Marshall
the surface.When William
wrote, the
extent and variety of workable
deposits in east
Norfolk was already well known from exposures
in existing marl pits, and attention was being
directed to using the material as effectively as
possible.
In the second half of the eighteenth century in
still regarded as a
west Norfolk marling was
asserted that
Young
Arthur
pioneering activity.
the high standard of farming forwhich that part
H. V.:
H. W., and Garner,
31) More
recently Gardner,
1953.
London
in British Agriculture.
of Lime
Use
of
a number
indicators
names
reliable
of other
28?31,
are common
in Britain,
sheep's
including
acidity which
sorrel
arvensis) and
{Rumex
spurrey
acetosella)y
(Spergula
knawel
{Scleranthus annuus and perennis).
The
repeated digging.
The benefits of marling were never so widely
as theywere during the first half of the
publicised
nineteenth century. In 1811 claying was recom
it was
to improve fen peat, although
mended
from trenches rather than deep
obtained
generally
of the Agriculture
View
General
Arthur:
32) Young,
1804.
402. Other
London
of Norfolk.
of the County
476.
on pp. 364, 366, 402?412,
to marling
references
the
Tour
Farmer's
Arthur:
The
through
33) Young,
1771. ii: 17,31,40,152?156,161.
London
East of England.
to place and
from place
in quantity
varied
34) A "load"
in the early nineteenth
time to time, but inNorfolk
century
to be about
36 cubic
reckoned
it was generally
feet, or
1% tons.
iy3 cubic yards, or approximately
Arthur:
op. cit. 1804, 402.
35) Young,
Hugh
C. Prince:
Pits and Ponds
inNorfolk
23
the
Withers
advocated
pits36). In 1826 William
eredadequate. This view was supported by Barugh
use of marl to promote the growth of trees on
Almack who stated that itwas better to claymore
poor light soils37). But these were small extensions
frequently than to run the risk of putting on too
a quantity at once41). But he weakened
was strongly
of a well-established
which
his
large
practice
a
the
of
writers
"as
foremost
the
argument by selecting,
urged by
agricultural
favourable specimen
and
period and actively encouraged bywealthy improv
of what has been done for the soil ofNorfolk,
to account for its present productive state", a 287
Coke
ing landlords such as Thomas William
of Holkham38).
acre farm at South Runcton
on which no less
farms in west Norfolk
Most
were occupied
interests in
than 54,055 loads of clay had been spread at one
by tenants whose
improvements were protected by long
making
dressing, an average of 188 per acre42). Again, at
two farms inWest Lexham, light sandy soils were
leases. During
the period of a 21-year lease an
initial outlay of less than fifty shillings per acre
clayed at the rate of 40 or 50 loads per acre, and at
return by ensuring high
secured a handsome
another near Swaffham, on the edge of the Breck
land, at the rate of over 80.
yields. In other parts of the county, where leases
seem to have been
The digging of marl ceased in most parts of
granted for short periods,
tenants were
less certain of a return on their Norfolk before the First World War, after declin
investment; but the existence of many thousands
ing for about half a century. H. B. Woodward'j*
of pits inmid-Norfolk and south Norfolk suggests
report on the geology of the country around
that farmers willingly ventured their capital in Fakenham, Wells
and Holt discusses marling as
if it were
still practised
there in 188 443); but
marling enterprises with confidence.
R. N. Bacon, writing in 1844, firmly advocated
for other districts
survey memoirs
geological
the use of marl or clay39). In his opinion, no
leave no doubt that itwas almost discontinued44).
If lime in some form was to be used at all, itwas
county "has been indebtedmore, if so much, tomanures
as
a
none
its
and
has
subsoils, Norfolk,
obtainedfrom
by
evidently cheaper to bring it from a distance than
larger quantity been used, or with greater increase of to dig it on the farm45).
The practice of marling has now been entirely
production"*?). The practice was
evidently still
a
at
extended.
A
of
farm
Castle
Acre
of improving soil
map
being
superseded by other means
texture and correcting
(Fig. 20) containing 46 fieldsmarks 35 "new" and
acidity, notably by the use
17 "old" marl pits; another of a farm atWeasen
of pure lime or chalk. Since the passing of the
ham (Fig. 19) containing 26 fields shows 25 "new"
Agricultural Act of 1937, which authorised the
and 10 "old" pits; yet another of a newly enclosed
payment of subsidies on lime delivered to a farm,
farm atMileham
shows several new pits dug there much has been done to restore the losses caused
in the course of improvements after 1814. In the
more
than half a century of neglect. The
by
Loam Region marl and chalk were being shipped
subsidy, paying half the cost of the material and
in small wherries from staithes near the pits, and
its delivery but nothing
towards the cost of
in many areas farmyard manure was being com
use
the
favours
of light dressings of
spreading,
lime or chalk rather than heavy dressings of im
posted with marl.
The dressings of marl or clay recommended by
farmers in the
pure marl dug on the farm.Many
are smaller than those
at
Bacon
now
district
Fakenham
obtain
kiln-dried
generally applied
ground
the beginning of the nineteenth century, partly as
chalk fromWells;
others use small lump chalk or
a measure of economy, and
lime waste from beet sugar factories. These ma
partly because itwas
then recognised that excessive applications were
terials are light, easy to handle and can be spread
harmful to the land. On light soils from 30 to 40,
bymanure drill or rotary spreader. Moderate dress
on
not
on
soils
than
less
and
40,
heavy
newly
broken land upwards of 100 loads were consid
Barugh:
On
the
of
R.:
General
View
of the Agriculture
of
36) Parkinson,
of Huntingdon.
the County
London
1811. 299, cited in
H. C.:
The
of the Fens,
2nd.
edit.
Darby,
Draining
1956. 238.
Cambridge
to the
A Memoir
William:
addressed
37) Withers,
... on the
for the Encouragement
of Arts
Society
Planting
of Forest-Trees.
and Rearing
Holt
1826. 18.
to by
is frequently
alluded
38) The marling
activity
and highly praised
R. N.,
Young,
Arthur,
by Bacon,
but Rigby, Edward:
its Agriculture.
Norwich
Holkham,
1818, does not refer to the practice.
on the
R. N.:
The Report
of
39) Bacon,
Agriculture
Norfolk.
on pp. 7, 94,
London
1844, discusses
marling
290?293.
267?273,
40) Ibid, 267.
41) Almack,
Journ. Roy. Agric.
42) Ibid, 312.
Soc.
5, 1845.
Norfolk,
Agriculture
307?357,
esp. 307?313.
H. B.: The Geology
of the Country
43) Woodward,
around Fakenham,
Wells
and Holt.
London
1884. 21?22.
H. B.: The Geology
of the Country
44) Woodward,
around Norwich.
London
1881. 115; Reid,
C.: The Geo
around Cromer.
1882. 3, 132;
London
logy of the Country
F. J.: The Geology
of the Country
around Attle
Bennett,
Watton
and Wymondham.
London
1884.
borough,
9;
The Geology
of the Country
around East
Blake,
J. H.:
Dereham.
London
1888. 51; Whitaker,W,
Skertchly,
S. B.J.,
and Jukes-Brown,
A. J.: The Geology
of the
of the Wash.
Borders
London
1899. 74.
Samuel:
Ancient
and Mo
45) Copland,
Agriculture,
dern :A Historical
Account
of its Principles
and Practice,
I. London
1864. 694?699,
774.
24 Erdkunde Band XVI
more than three to eight tons per
ings of not
acre, depending on the acidity of the soil, may be
ten years.
expected to benefit the land for at least
On light sandy soils with a pH value as low as
4.6, a single dressing of five tons of soft lump
chalk is sufficient to ensure normal crops of sugar
than
beet and other sensitive plants for more
In 1950 a total
17 years in this part of England46).
of 228,156 tons of liming materials was consumed
inNorfolk, or about 4% cwt. per cultivated acre,
which was
rather more
than the average
for
and Wales47).
England
The evidence formarling in the eighteenth and
nineteenth century is abundant and decisive. Estate
accounts, surveys and the reports of contemporary
show that many pits and ponds owe
observers
their present form to the digging of mineral
manures.
Shallow depressions
The evidence for marling does not dispose of
the problem of the origin of hollows. It does not
tell us whether the pits we see are entirely man
made or natural hollows deepened by digging.
Several agricultural writers have noted that the
surface of the ground was patterned with broad
shallow hollows before marl pits were excavated.
Thomas Hales writing in 1756 believed that such
hollows marked the sites of former diggings and
he instructs the reader, "When he hasfound any such
Hollows
let him mind theCourse wherein theyrun,for
runs also"*8).
thatWay probably theVein ofMarie
Hales
draws upon a wealth of oberservations
made in theMidlands
and southern England, but
does not refer specifically to Norfolk. That Nor
folk also had a pitted surface in the early eight
eenth century is confirmed by an account of
husbandry inNorfolk in 1752. It states, "we have
an abundance of oldpits, and many
of them have gone
name
the
marie
and
inclosures
have been
by
of
pits,
denominatedfrom them above two hundred years"**).
It is clear that at least some eighteenth century
marl pits were dug on a pitted not a smooth sur
face, and because some of them were named marl
pits it was assumed that they had been dug for
that purpose at some earlier period. But a great
many hollows bear names which do not tell us
A. W.,
and Garner,
H. V.: Light Land
46) Oldershaw,
at Tunstall,
Suffolk. Journ. Roy. Agric.
Soc.
Experiments
and Garner,
H.V.:
105, 1944. 98; Oldershaw,
A.W.,
on Light
at Tunstall.
Land
Journ.
Liming
Experiments
Soc.
110, 1949. 89.
Roy. Agric.
Lime Depart
47) Statistics collected
by the Agricultural
ment of the Ministry
of Agriculture,
cited in Gardner,
H. W.,
and Garner,
H.V.:
The Use of Lime
in British
London
1953. 197.
Agriculture.
Thomas:
A Compleat
of Husbandry.
48) Hales,
Body
London
1756. 46.
in Norfolk.
The
state 0f Husbandry
Gentle
49) ?N?.
man's Magazine
22, 1752. 453.
such as Hell Pit,
they originated. Names
Hole and Thief's
Smokers
Hole,Dunfer
Pit,
Hag's
Pit tell us only that they have been landscape
features since their names were first recorded.
Early estate maps likewise show thatmany hollows
existed in the sixteenth and seventeenth century,
not how they came to be there. On
the other
hand, eighteenth and nineteenth century records
fail to state precisely the location of the pits.
state what quantities
Account
books generally
were spread on a particular farm, but rarely from
which field the material was obtained. Again,
for
less documentary
evidence
there is much
areas
in
the
in
mid-Norfolk,
densely pitted
marling
east of Attleborough,
Dereham
and Fakenham,
than in west Norfolk. All that can be stated with
certainty from available historical records is that
many hollows of uncertain origin existed inNor
how
\
^
7%./
//
Pits and ponds
_440
?^
Depressions
AlethorpeHalL/5
Wood
yards_j
near
and shallow depressions
ponds
Hall.
Alethorpe
on examination
ref. 125/950310.
Grid
Based
of
air photograph
Air Ministry
taken in 1946
and field survey in August
1958.
Fig.
17: Pits,
Hugh
Table
IV:
C. Prince:
of pits marked
Comparison
GREAT MAS SINGHAM
Cu
on
^
o
a
Pt g
1946
H
~
?.2
air photographs
CASTLE
s
g
c?
\o
c/)r-< cn o
Pm g
H
S
9
3
0
1779 Pits
1
0
0
1
5
2
3
10
1844Old Pits
1
2
7
10
1844Old Pits
1884NewPits
24
1
1
26~
1844NewPits
17
7
1
25
1844NewPits
photographs
0
38
17
23
14
11
1946
early
33
photographs
20
S2 ^
a>2 81 Ii4
ag
1833NewPits
1946Hollows
not shown on
earlymaps
Total shown
on 1946 air
?a
g
?? si
1728-44 Pits
1946Hollows
not shown on
earlymaps
Total shown
on 1946 air
0
a.'^wco\ow
^^O.v.TJc"^
g* 8g ag
.s&
g"3 si
S
ACRE
^
o
^^3Q.tJ^G
?| .SSg-3 ss ?-? a?
c/}t-h c/} o
on
shown
?? ?1 SS I
%
"d
25
WEASENHAM
.2 ^
Q.i
those
with
early maps
c&Sogsg
a?
inNorfolk
Pits and Ponds
(^th
cfl o
3
2
~~2
7"
3
6
20~
17
10
8
35~
15
16
46
31
1779 Pits
Hollows
not shown on
maps
Total shown
on 1946 air
photographs
U
Pt g
H
S
folk at the end of the sixteenth century; and a
are still
hollows
12 pits
steep-sided pits. Of
marked on a map of 1728?1744,
9 are pits at the
great deal of marl was dug from unidentified pits
in west Norfolk during the eighteenth and nine
present time, and the others can be recognised as
teenth century.
shallow depressions.
If evidence for the other
In north-west Norfolk close inspection of the
two estates were as clear as thiswe
might conclude
reveals that
that a large number of shallow depressions
ground and recent air photographs
origi
in addition to steep-sided pits and ponds there are
nated before eighteenth and nineteenth century
is much
less certain at
many broad shallow depressions which are plough
marling
began. This
ed over and cultivated
shallow
Weasenham
of R. N.
(Fig. 17). The
(Fig. 19). A comparison
to
be
rounder
and
Bacon'jin
recent
1844
with
air
smoother,
appear
depressions
map
photographs
shows that almost half the present pits are not
generally larger than the steep-sided pits, which
are occasionally
situated within them or at their
recorded in 1844, and 8 out of 35 pits marked on
the 1844 map cannot be located on air
edges. They may be explained in two different
photo
ways: either theymark the sites of man-made pits
graphs. Digging
during the past century may
that have been abandoned
and perhaps deliber
account
for some new pits
on air
appearing
but how are the 8 missing nine
ately filled in; or they are natural hollows. If they photographs,
are filled-in pits we may expect to find some of
teenth century pits to be accounted
for? If we
them marked as pits on early maps;
dismiss the possibility that the surveyor errone
indeed, all
pits marked on early maps, except those obliter
ously recorded non-existent pits,we must acknowl
ated by buildings,
embankments
and cuttings,
edge that not all hollows or traces of hollows
either may be detected on air
Some may
ought to be discernible on air photographs
photographs.
as pits or as shallow
be concealed by crops or woodland
depressions.
vegetation,
Recent air photographs
of parts of three west
others may have been completely erased
by filling
Norfolk parishes show that steep-sided
are
and cultivation. At Castle Acre
in, weathering
pits
about 50% more numerous than shallow
depres
(Fig. 20), 16 pits marked on early surveys are not
sions (Table
but whereas
about
three
shown on air photographs,
and nearly one-third
IV);
of the present pits are not
quarters of the present pits can be identified on
previously recorded.
and Castle Acre over half
early estate maps, only about two-fifths of the At both Weasenham
are
shallow depressions
the present shallow depressions are not accounted
represented. At Great
are
all
for on early maps. Some, if not all these, may be
Massingham
present day pits
(Fig. 18),
recorded on previous surveys, but only 6 of the
filled-in pits dug before the
eighteenth century,
are
but some may well be the result of natural pro
present 23 shallow depressions
previously
as pits or
Some of the oldest
cesses.
mapped
ponds.
26 Erdkunde Band XVI
Sink Holes
Solution or ice action may have contributed to
the formation of depressions. The presence of
sink holes due to solution of calcium carbonate
by rainwater and other weak acids, and the col
cavities is
lapse of the surface into underground
suggested by the fact that chalk lies beneath the
most densely pitted parts of Norfolk.
Pipes,
subsidences and the Breckland meres are cited as
visible evidence of the effect of chemical weath
ering.
have been described
Enclosed
depressions
as the fundamental and essential units
repeatedly
of limestone topography and are also charac
teristic of the English chalklands50). In Norfolk
most hollows lie to the east of the chalk outcrop
and are underlain by chalk at depths increasing
to about
from a few inches in the Breckland
and Cromer. East of
100 feet between Norwich
the chalk plunges beneath a thick cover
Norwich
and more recent crag formations to a
of Eocene
There
almost
600 feet at Yarmouth51).
of
depth
are very few hollows in the eastern coastal areas,
but no less than 2000 in the west lie beyond the
Belt. Many of
edge of the chalk in theGreensand
the latter are situated on intensely chalky boulder
as much calcium carbonate
clay containing almost
as chalk itself and similarly subject to chemical
The few hollows present on ex
weathering52).
and other non
Lower
Greensand
of
posures
calcareous rocks older than chalk are unlikely to
sink hole
have been formed by solution. The
claim to account for
cannot
therefore
hypothesis
all hollows. Again, if solution features are formed
in solid chalk they should be most numerous in
the Breckland where the chalk lies close to the
effect of
surface and is exposed to the maximum
processes.
or
undoubtedly produced the vertical
in quarries and other
exposed
pipes
diagonal
sections cutting through the chalk53). Varying in
size from 6 inches to 100 feet across, they are
filledwith material derived from overlying strata
weathering
Solution
in Corbel,
fullest recent account
appears
Jean :
50) The
et de quelques
de P Europe
karsts du nord-quest
Les
1957.
Rhodan.
Inst. Etudes.
Lyon
regions de comparaison,
The
and
W. G. V.:
and Balchin,
origin
Coleman,
A.,
Hills.
in the Mendip
of surface depressions
development
reviews English
Assoc.
Proc. Geol.
70, 1959. 291?306,
studies
of karstic
depressions.
W.:
Austin
from under
Water
Supply
51) Woodland,
district. Geological
sources of Cambridge-Ipswich
ground
I?X.
London
Parts
Wartime
20,
Pamphlet
Survey
in south
of well
details
borings
1942?1946,
provides
Norfolk.
of the Country
The Geology
H. B.:
52) Woodward,
1881.
London
Mem.
Geol.
Norwich.
around
Survey.
chalk
of pipes in glaciated
120, 134, refers to an abundance
and
chalky boulder
53) Woodward,
clay.
H. B.:
op.
cit. 1881.
9.
or from the surface soil. Nests of gravel or coarse
sand, known locally as "sand galls", are a distinc
tive feature ofNorfolk pipes54). The surface above
is sometimes level with the surrounding country
but sometimes forms a circular depression several
feet in diameter. Depressions
may be smooth and
or
and fissured where
in
broken
outline,
regular
recent subsidence has disturbed the surface.
Sink holes may subside with dramatic sudden
ness. H. B. Woodward
reports many eye-witness
accounts of hollows
in the country
appearing
and similar incidents in other
around Norwich,
in past centuries are
parts of Norfolk observed
A "cave in"
recorded byWilliam
Whitaker55).
a farm cart
of
the
be
may
passing
precipitated by
or a heavy downpour of rain, and may be accom
an eruption of water displaced by the
panied by
sudden fall of earth from the roof of a cavity. By
contrast, the ground may subside slowly over a
area. This
is
Mere
is how Mannington
wide
to
in
Sub
have
170456).
originated
reported
sidence may be a result of human activity caused
by the collapse of galleries of ancient flint mines
and bell pits, producing a pitted surface like that
at Grimes Graves near Brandon or Broom's Hill
near Thetford57).
The steep-sided circular or elliptical meres in
have been described as "swallow
the Breckland
holes due to solution of the chalk, and possibly in some
cases collapse of the surface intounderground cavities"58).
The largest of these hollows are situated on a
flat surface some 120 to 180 feet above sea level
the chalk is very thinly covered with
where
of sand, flint gravels and yellowish
deposits
meres such
boulder
clay. Between the large
chalky
are
of
small de
as Fowlmere
hundreds
(Fig. 21)
one acre in extent, but similar
pressions, less than
an area of three square miles
in form. Within
lie 50 such hollows which are
around Fowlmere
54) Woodward,
2nd. Edit.
Wales.
H. B.:
London
The Geology
1887. 422.
of England
and
and Subsidences
H. B.: Earthquakes
55) Woodward,
Naturalists'
and Norwich
Trans.
Norfolk
in Norfolk.
H. B.: Geology
Woodward,
3, 1884. 637?643;
Society
1912.
London
of Soils
and Substrata.
64; Whitaker,
Geol.
of Norfolk.
The Water
William:
Survey
Supply
1921. 40.
London
Memoir.
H. B.:
loc. cit. 1884. 641.
56) Woodward,
in the gravel of
some cavities
Sir John: On
57) Evans,
Geol.
in Norfolk.
the valley of the Little Ouse
5,
Mag.
London
East
R. R.:
1868. 443?447;
Clarke,
Anglia.
1960. 51?58.
in
levels
Water
and Lewis, W.V.:
O.T.,
58) Jones,
and other Breckland
Fowlmere
meres, Geog.
Journ. 97,
to the earlier work done by
is made
1941. 158. Reference
Phil.
Proc. Camb.
of Breckland,
Marr,
J. E.: The Meres
that the meres
which also concluded
Soc. 17, 1913. 58?61,
as solution
depressions.
originated
Hugh
Fig. 2l:
Air
view
C. Prince:
Pits and Ponds
of Fowlmere.
Grid ref. 136/879895.
(Photo
J. K.
S. St. Joseph,
copyright
reserved)
in
also claimed to be sink holes59). Fluctuations
the level of water in these meres are related to
water in the
long-term changes in the height of
are presumed
underlying chalk, from which they
to be fedby pipes.
Apart from the sink holes in the Breckland few
in Norfolk
hollows
penetrate deeply into solid
there
is
little
evidence that any solution
and
chalk,
took place in the long interval between the end
times and the beginning of the
of Cretaceous
It has long been noted that pipes
Pleistocene.
examined in chalk quarries contain few traces of
material derived from strata older than glacial
the oldest solution features in
drift60). Among
are the tubular stacks on the coast at
Norfolk
Crag
Sheringham, containing sand ofWeybourne
was initiated
age61). If the formation of hollows
by solution we should expect to find evidence of
and later times,
the process at work in Eocene
because the surface of the Upper Chalk appears
not to have been bevelled, nor can it have lain
below water throughout this period.
Kettle
holes and thaw sinks
Almost all the hollows inNorfolk are situated
in areas covered by glacial drift. They are most
numerous where the drift attains a thickness of
more than ten feet, least numerous where
it is
and Lewis, W.V.:
loc. cit. 166.
59) Jones, O.T.,
:On
Osborne
the Denudations
of Norfolk.
60) Fisher,
Geol. Mag.
5, 1868. 546.
T.
P.:
The
Tubular
chalk
stacks
of
61) Burnaby,
Proc. Geol.
Assoc.
61, 1950. 226?241.
Sheringham,
inNorfolk
27
thinnest. They occur infrequently on older forma
tions, and are absent from areas covered by post
glacial deposits of peat and alluvium. The pos
sibility that they were formed under glacial or
periglacial conditions cannot be ignored..
Under glacial conditions kettle holes may be
formed by detached masses of stagnant ice em
bedded within the drift melting slowly to cause
a gradual
of the surface62). Such
subsidence
are frequently larger in size than the
hollows
majority ofNorfolk hollows, and also irregular in
are characteristic features of outwash
shape. They
not
boulder
clay plains such as those of
plains
Norfolk. They frequently follow the courses of
buried pre-glacial valleys as kettle-chains; whereas
the majority of hollows
in Norfolk are situated
on flat interfluves.
In 1868 Osborne
Fisher
suggested a glacial
meres on the
some
the
for
of
Breckland
origin
an
basis of his examination of Rockland Mere,
enclosed depression about 8 feet deep, excavated
in boulder clay63). The floor of themere is covered
with unsorted masses of clayey gravel and large
flints derived from the boulder clay, upon which
lies a layer of peat. The validity of the glacial
on two essential conditions:
hypothesis here rests
that the hollows are cut entirely into glacial drift;
and that they have been produced during the last
glaciation of the district because hollows formed
during the deposition of older drifts would have
been filled in or modified by erosion during sub
sequent glaciations. It is now established that nei
ther of these conditions is fulfilled in theBreckland,
nor in other parts of the county. The floors of sev
eral meres notch the surface of the chalk, below the
level of theglacial driftwhich might have contained
embedded ice masses. The meres also lie beyond
the limit of most recent drift deposits in north
are most
Norfolk.
Indeed, enclosed depressions
numerous in areas of Lowestoft
till and are pres
ent in areas of yet older North Sea drift.
If hollows were formed after the glacial drifts
had been laid down, their presence in older as
for. In
well as newer drift might be accounted
and
France,
Poland, Germany, Holland, Belgium
situations in England,
yet not in comparable
hollows similar to those in Norfolk have a peri
glacial origin ascribed to them64). In order to
62) Their mode of origin is discussed at length in
F.T.:
Outline
of Glacial
Madison
Thwaites,
Geology.
and Thornbury,
William
D.:
1953, 47?49,
Principles
New York
of Geomorphology.
1954. 392.
loc. cit. 1868. 557?558.
Osborne:
63) Fisher,
are cited in Cailleux,
to previous
work
64) References
Andre:
Les mares
du sud-est de Sjaelland,
Danemark.
S. R. S. de l'Acad.
Sciences
and
1074?1076;
245, 1957.
Les
A.:
ferm?es de la region pari
Pissart,
depressions
sienne. Rev. Geom.
9, 1958. 73?83.
Dyn.
28 Erdkunde Band XVI
!
^1833^
1728-44
"^^^^^^^^
^^^^^^^^Oid Pits
one mile
i-.
1884
^ C> Old
Pits
A New Pits
Based
*
New
Pits
1946
'
Pits
O
Depressions
at Great Massingham.
Fig, 18: Pits, ponds and shallow depressions
on Holkham
Estate maps
1759, 1779, 1833), Ordnance
(1728-44,
Survey
and air photographs
(1946).
maps
(1884)
Hugh C. Prince: Pits and Ponds inNorfolk 29
^^^^^^^^^^^^
j^^^^^^^^-^j
^-JJ
I-Former
Based
on Holkham
Based
Depressions
Fig. 20:
Estate
^*-U
inWeasenham.
and air photograph
(1844)
o
Depressions
at Castle Acre.
Pits, ponds and shallow depressions
and air photographs
maps
map
(1779), R. N. Bacon's
(1844)
data on
in the drift
disturbances
superficial
in the nineteenth
has
been
century
largely
in recent
re
sutdies
and might
prove worth
neglected
in
the light of present knowledge
of periglacial
examining
a
Such notes
in Taylor,
appear
phenomena.
J. E.: On
of the chalk at Whitlingham.
Geol. Mag.
2,
displacement
(1946).
^^19^
New Pits
^ * Pits
,_,
Fences
establish a relationship between the continental
hollows and those inNorfolk we must determine
their age. Stratified deposits of mud, fossil soils,
peat containing appropriate flora and fauna have
not yet been examined in this context, but evi
dence for other forms of periglacial
action in
Norfolk is accumulating. Festooning
and contor
tions in the drift have been widely reported and
.
extensively discussed65). An explanation proposed
65) The
collected
?
|
^ ^1844^
*
-Former
on Holkham
'
'
Fig. 19: Pits, ponds and shallow depressions
Estate maps
map
(1779), R. N. Bacon's
1779
one mile
Fences^^Lj
(1946).
a disturbance
1865. 324; Taylor,
of the chalk
J. E.: On
at
Geol. Mag.
3,1866.44;
Fisher,Osborne:
Swainsthorpe.
On
the Warp
con
its age and probable
(of Mr. Trimmer),
nection
events. Quart.
with
the last geological
Journ.
a
Geol.
Soc. 22, 1866, 553?565;
S. V.,
Wood,
Jun: On
at Litcham
section
evidence
of land glaciation
affording
the earlier part of the glacial
in England.
during
period
Geol.
S. V.,
4, 1867,
78?79;
Wood,
Mag.
Jun: and
F. W.:
The glacial
structures of
and post-glacial
Harmer,
Norfolk
and
Geol.
Suffolk.
5, 1868.
452-456;
Mag.
a
instance of interglacial
Wood,
S.V.,
Jun: On
peculiar
near Norwich.
erosion
Geol.
6, 1869. 226?227;
Mag.
On
certain phenomena
in the drift near
Taylor,
J. E.:
Norwich.
Geol.
6, 1869.
508?509;
Woodward,
Mag.
a distrubance
at Trowse
near
H. B.: On
of the chalk
Norwich.
Geol.
II 6, 1879. 380; Wood
Decade
Mag.
in the chalk of Norfolk.
H. B.: Disturbances
Geol.
ward,
II 8, 1881. 93?94.
Decade
Mag.
30 Erdkunde Band XVI
during the nineteenth century was that theywere
formed by pressure and displacement by ice and
Slater
in
drift, but George
superincumbent
1926 demonstrated that this explanation failed to
account for the whole structures and preferred to
interpret them as features of "fossil glaciers"66).
The "erratic warp" and "trail" of coarse materials
filling throughs and hollows are now considered
and others
S. E. Hollingworth
by G. G. Dines,
to be solifluction
of
detached
deposits composed
and comminuted
rocks rearranged
after the
thawing of ice67). Fossil ice wedges, polygonal
structures and solifluction deposits are described
in the Cambridge
region68). Stone stripes are
In other parts of
observed in the Breckland69).
southern England
and theMidlands many com
as
parable surface features are now identified
peri
for
The
such
condi
evidence
glacial phenomena.
tions having existed inNorfolk is beyond reason
able doubt.
Circular or elliptical depressions ranging from
10 to 1000 feet across are characteristic of areas
in Siberia and
of perennially
frozen ground
Alaska70). They are most frequent on flat surfaces
and are not known to occur on slopes of more
are most numerous where
than 5?. Depressions
the top of the perennially frozen zone, the tjaele,
lies between
10 and 75 feet below the surface;
none occur where the frozen ground ismore than
are observed
in
100 feet below71). Depressions
loams
fine
residual
lake
silts,
soils,
clay
clays,
deep
and other fine-grained porous materials. They
are not found in gravel.
rarely occur in sands and
Silt, which in its unfrozen state has a porosity of
about 20?30%,
may contain as much as 80% ice
when
volume
frozen72). It is banded with
by
horizontal
layers of clear ice, sometimes in the
broken
form of tabular or lenticular masses,
as reflected
in
Glacial
tectonics
George:
66) Slater,
Assoc.
Proc.
Geol.
drift deposits.
disturbed
37, 1926.
392?400.
S. E., Edwards,
H. G., Hollingworth,
W.,
67) Dines,
of head de
F. B. A.: The Mapping
Buchan,
S., Welch,
77, 1940. 202?203.
posits. Geol. Mag.
and
The
T. T.:
effects of frost action
68) Paterson,
dis
around Baffin Bay and in the Cambridge
solifluxion
Soc. 96, 1940. 99?130.
trict. Quart.
Journ. Geol.
Norfolk.
A. S.: Stone
stripes in Breckland,
69) Watt,
173.
Cours
de
Jean: Le Modele
periglaciaire.
reviews
T.
II, i. Paris n. d. 230?234,
im
the most
of periglacial
depressions,
Thaw
lakes and thaw
M.:
David
portant being Hopkins,
Alaska.
sinks in the Imuruk Lake
area, Seward
Peninsula,
57, 1949. 119?131.
Journ. Geol.
a
on Alaskan
W. A.:
farmlands,
Pitting
71) Rockie,
Rev.
new erosion problem.
32, 1942. 134.
Geog.
in
frozen
Stephen:
Perennially
ground
72) Taber,
Soc. America
its origin and history. Bull. Geol.
54,
Alaska,
Geol.
92,
Mag.
70) Tricart,
geomorphologie.
recent accounts
1943. 1518.
1955.
by ice veins or wedges73). Horizontal
tend to concentrate in the upper layers
ground and may coalesce with the thick
ice wedges.
In fine-grained materials
highly charged with ice any difference in the rate
and depth of thawing may be expected to produce
local
in volume.
subsidence
from shrinkage
Differences in the thermal conductivity of bodies
of peat, silt, gravel, ice or water in the surface
cause differences in the depth of
layer would
illustrates a hypothetical
thawing74). Hopkins
of
frozen
example
ground initially blanketed by
a well insulated layer of peat, in which a distur
bance of the peat by frost heaving, exposes a patch
of bare ground. The greater conductivity of the
bare ground results in deep thawing and conse
collects in this hollow
quent subsidence. Water
and further increases the extent of thawing. Small
areas of exceptionally deep thaw tend to be self
perpetuating and self enlarging and may even
tually penetrate beneath the zone of permanently
frozen ground to form thaw sinks of great depth
and funnel like shape. Hopkins
believes that the
form of such hollows "could be achieved only by the
removal of considerable material from thefloor" hy
small streams carrying it into subterranean chan
nels below the frozen zone75). If underground
a
drainage takes place the presence of permeable
substratum below the frozen zone is assumed.
in
In shape and size the hollows
observed
in
and
those
resemble
Alaska
Norfolk,
closely
hollows
their situation is comparable. Norfolk
on level or gently sloping
are most
frequent
are absent on recent deposits of
ground. They
peat and alluvium and are densely concentrated
on the retentive boulder clay soils of mid-Norfolk
and south Norfolk. An appreciable number, how
ever, occur in west Norfolk where the chalk is
thinly mantled with sand. It is possible that the
finely disintegrated frozen chalk, often described
as disturbed or glaciated
by Norfolk geologists
some
have
would
chalk,
capacity for holding
or clay. The under
silt
less
than
ice
but
ground
a
also provide
permeable
lying chalk would
substratum into which thaw sinks might drain.
to be almost as
Many Norfolk hollows appear
as those observed inAlaska;
deep and steep-sided
hollows are now being formed
but the Alaskan
vertically
ice lenses
of frozen
ends of
L.: Glaciation,
depth of frost and ice
73) Wernecke,
and vicinity, Yukon
Hill
veins of Keno
Eng.
Territory.
and Mining
Journ. 133, 1932. 41.
in un
Earth mounds
A. E.:
Porsild,
7i) Conversely,
Rev.
America.
arctic northwestern
28,
Geog.
glaciated
in the rate of ice
that differences
1938. 46?58,
suggests
ice
accumulation
ground
may cause upheaval,
producing
ice mounds
or pingos.
P.: Ground
mounds
Sharp, Robert
adds that
Rev.
in the Tundra.
32, 1942. 417?423
Geog.
accounts
for the small
ice mounds
of ground
the collapse
of the tundra surface.
characteristic
pools
David
M.:
loc. cit. 1949. 130.
75) Hopkins,
C. Troll:
"Solle"
frozen
by periodic
thawing above perennially
In
ceased
Norfolk
the
has
ground
long
ground.
to be deeply frozen and we must consider what
as a result of
changes may have taken place
complete thawing. If fine-grained materials shrink
and subside uniformly on thawing, the result of
complete thawing may be to equalise the local
differences initiated by uneven thawing. In other
words, we should expect remnants of frozen silt
eventually to subside to more or less the same
over
level as the original depressions.
Only
the
of
thaw
sinks
because
may persist
deepened
streams
their
of
floors
by
underground
sapping
to exist in a permeable substratum.
presumed
If thaw sinks initiated by mechanical processes
under periglacial
conditions
survived eventual
thaw of ground ice theymay have become greatly
under colder
enlarged by chemical weathering
climatic conditions than those now prevailing76).
Solution varies directly with the amount of water
and carbon dioxide available, and these are pre
sent in greater quantities under cold conditions
than warm. Air within a snow bank is concen
rain or meltwater
trated with carbon dioxide;
passing through snow is at the optimum tempera
ture for absorbing
it; and the ground beneath,
while unfrozen, is likely to be nearly saturated. In
Chemical
76) Williams,
Joseph E.:
Rev.
39, 1949.
temperatures.
Geog.
op. cit. 1957. 11, 496.
Jean:
weathering
129?135;
"SOLLE"
Glacial
and Periglacial
at low
Corbel,
AND
and "Mardelles"
carbonate
the solubility of calcium
addition,
increases very slightly with a decrease in tempera
ture. Under the present warm dry climate of Nor
than
folk solution must operate less vigorously
formerly, yet it is still evident. It is possible that
many natural depressions originated under peri
were enlarged by chemical
glacial conditions and
weathering.
Conclusions and conjectures
from the distinctive irregular modern
Apart
and
quarries
large circular Breckland meres, the
and
appear to be much
ponds of Norfolk
pits
alike in shape and size. What distinguishes them
is their uneven distribution: their presence upon
glacial drifts, their absence from recent peat and
on heavy land,
their concentration
alluvium;
their sparseness on light land; their abundance on
flat surfaces, their fewness on steep slopes. No
accounts
for all
single explanation
adequately
in these different situations. It seems
hollows
certain from historial evidence thatmany pits owe
their present form to man's
activity, either as
mineral workings or as marl pits. It may yet be
proved thatmost marl pits have been dug on the
sites or depressions which originated under peri
or on hollows formed by the
glacial conditions
solution of underlying chalk or chalky drift. In
that case it may be demonstrated
that man has
merely adapted these hollows for his own use.
"MARDELLES"
Phenomena
Carl
in der
und
,,Solle"
,,Mardellen"
Zusammenfassung:
Glazialund
des
festlandischen
Periglaziallandschaft
Europa.
Die meisten
C. Prince
der von H.
im vorstehenden
aus Norfolk
Artikel
beschriebenen
Hohlformen
ent
den
Sollen
der nordmittel
sog.
sprechen
(Sing.
Soil)
sie gibt
Ober
Grundmoranenlandschaften.
europaischen
es eine ausfuhrlichere
altere Literatur,
die von W. Ropke
wurde.
Von
den Moglichkeiten
(1929)
zusammengefaBt
waren
der Erklarung
zwei noch
in neuerer
Zeit
iibrig
die Solle als subglaziale
Strudellocher
oder als
geblieben:
Die Erklarung
Toteiskessel.
durch Toteis-Ausschmelzung
war
von
zu
Ropke
der
?Intramoraneneis-Schmelz
theorie" variiert worden.
Der Toteistheorie
steht entgegen,
daB die in geschichte
ten fluvioglazialen
ein
vorkommenden,
Ablagerungen
wandfreien
Toteisformen
meist
verschieden
und
groBe
vielfach
Senken
unregelmaBig
sind,
geformte,
zerlappte
wahrend
die Solle
immer kleine,
kreisrunde
oder ovale
Kessel
darstellen.
Gerade
dies kann eine neue ?Pingo-Theorie"
erklaren.
von
Nach
ihr sind die Solle die Reste
Eis
periglazialen
die nach der
(Eskimoname
schwellungshugeln
?Pingo"),
eine kreisrunde Mulde
mit einem sie um
Abschmelzung
31
in Continental
Europe
Troll
flachen Ringwall
also Austauseen
hinterlassen,
gebenden
im Sinne vonD.
M. Hopkins.
Der Nach
(?Thaw
lakes")
weis dieser Entstehung
ist von Maarleveld
und van den
in hollandisch
Toorn
fiir ein Soil
in der
also
Friesland,
Altmoranenlandschaft
Fiir die Mardellen
gefiihrt worden.
des Pariser Beckens,
des Hohen
der Landes
und
Venns,
ist die neue Pingo-Theorie
ebenfalls
heran
Lothringens
Fiir die Solle
worden.
der Jungmoranenland
gezogen
in der Umgebung
schaften
der Ostsee
mufite man
bei
dieser Erklarung
dafi sich nach dem Ruckzug
annehmen,
des letzteiszeitlichen
in das Ostseebecken
Inlandeises
noch
Dauergefrornis
gebildet habe.
Most of the Norfolk pits and ponds described
in the preceding paper are
by H. C. Prince
circular or eliptical basins of regular
shape and
little extent, usually smaller than an acre.
They
to the "solle"
of the ground
fully correspond
moraines
of Northern
Central Europe,
which
are found all over the Netherlands,
Denmark,
Northern
and Poland.
"solle"
The
Germany