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Studies in Speleology Volume 17, August 2010, pages xx-xx
A GEOGRAPHIC INFORMATION SYSTEMS APPROACH TO
THE 19TH CENTURY EXCAVATION OF BRIXHAM CAVERN,
DEVON, ENGLAND
Donald A. McFarlanea, Joyce Lundbergb, and Warren Robertsc
a W. M. Keck Science Center, The Claremont Colleges, Claremont CA 91711 USA.
b Department of Geography and Environmental Studies, Carleton University, Ottawa,
ON K1S 5B6, Canada.
c The Claremont College Libraries, 800 N. Dartmouth, Claremont, CA 91711-3991
ABSTRACT
The oldest known spatially-explicit archaeological excavation, conducted in Brixham cave, Devon,
in 1858, is reconstructed using geographic information systems technology. Two dimensional
plots of individual fossil taxa and flint artefacts demonstrate the utility of the technique for
elucidating taphonomy and palaeobiology.The cave served as a den for hibernating brown bears,
as a den for hyena and cave lion, and as a reliquary for their prey.
INTRODUCTION
Brixham Cave (also known as Windmill Hill Cavern) is a small solutional fissure cave
located in the town of Brixham, Devon, England (Latitude 50.394 N, Longitude 3.513 W,
altitude 25 m). The cave was closed to the surface in modern times, until it was
uncovered during limestone quarrying operations on January 15th 1858. The landowner, a
Mr John Philp, noticed the presence of an antler lying on top of a flowstone floor some 23
m into the cave, and the discovery was communicated to William Pengelly shortly
thereafter. Pengelly recognised that the excavation of a pristine cave containing
paleontological remains might resolve one of the most important scientific and
philosophical questions of the mid-19th century – the contentious question of the
“antiquity of Man”.
Scientific study of European “bone caves” can be said to have been placed on a firm
footing with the publication of William Buckland’s Reliquiae Diluvianae (1824) in which
he noted at least eight instances in which human remains were found in cave strata
apparently coincident with the bones of extinct mammals. This juxtaposition challenged
the prevailing Natural Theology that had developed over the preceding century from the
intercalation of Biblical scripture and the emergent field of geology. Buckland, in keeping
with his deference to Scripture and a young age for the human species, argued that the
bones in these cave deposits were “....not of the same antiquity with those of the
antediluvian animals that occur in the same caves with them” (Buckland, 1824, p.169).
Others disagreed. John MacEnery began sporadic excavations in nearby Kent’s Hole
(now Kents Cavern; latitude 50.467 N, longitude 3.503 W, altitude 58 m) in the summer
of 1825, inspired by Buckland’s work and initially in the company of Buckland himself
(Kennard, 1945). By 1826 MacEnery had apparently satisfied himself that flint
implements and extinct mammals were contemporaneous, but he deferred to Buckland’s
opinion that they were emplaced in oven pits by recent Celtic occupants of the cave, and
withheld his manuscript on the subject from publication. The work was eventually
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DONALD A. MCFARLANE, JOYCE LUNDBERG and WARREN ROBERTS 2
published, posthumously, in 1859 (MacEnery, 1859) by which time it had been
superseded by Pengelly’s excavations in Brixham cave.
The significance of Brixham Cave in the spring of 1858 lay in its pristine condition
and the intact capping of flowstone that sealed the presumed ancient bones and tools from
historic-era intrusions. Convinced that the site could provide a definitive test of the
contemporaneity of the human artefacts and extinct mammals, the Geological Society of
London established a Brixham Cave Committee and obtained a grant from the Royal
Society to secure a lease to the cave (Gruber, 1965; van Riper, 1993).
The excavations, under Pengelly’s supervision, set a new standard for the science.
Whereas previous cave excavations had focused on simple collection of the materials,
Pengelly devised a system to associate each fossil and artefact with its spatial location in
the cave. Brixham Cave consists of a network of mostly narrow, rectilinear fissures
developed along the joints of the limestone bedrock. Pengelly’s excavation system was
two dimensional – position was recorded horizontally along the axes of the fissures, and
vertically through the strata. Axial position was defined as distance along a survey line
from the origin (the modern entrance) or the opening of subsequent galleries (fissures)
from the first fissure (the “Reindeer Gallery”; Figure 1). Some original survey line
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3 A GIS APPROACH TO THE 19TH CENTURY EXCAVATION OF BRIXHAM CAVERN
markings remain in the cave. Position left or right of the survey line was not recorded,
probably because of the narrowness of the fissures. When Pengelly began work on Kents
Cavern seven years later, the larger passages necessitated that he develop his system into
a true three-dimensional methodology (McFarlane and Lundberg, 2007), which became
the foundation of modern archaeological and paleontological excavation practice.
Although the Brixham Cave excavations convinced the excavators and their
collaborators that human artefacts were indeed buried in the cave coexistent in age with
extinct “antediluvian” species, an abundance of caution in London delayed formal
publication of the results until 1873, by which time more spectacular evidence had been
reported from Continental Europe (van Riper, 1993; Rudwick, 2008) and Brixham Cave
slipped into relative obscurity. Nevertheless, the thoroughness of the excavation records
and notes that have survived (Pengelly, 1873; unpublished Pengelly notebooks, 1858,
Torquay Museum) permit a re-examination of the spatial aspects of the data using a
geographic information systems (GIS) approach.
METHODS
The original cave survey (Pengelly et al., 1873) was digitized and imported into
ArcGIS v9 (ESRI, 2009) as a shapefile. Specimen data from Pengelly et al. (1873) was
transcribed into an Excel (Microsoft Corporation, 2007) spreadsheet and also imported
into ArcGIS v9. Specimen locations which were originally recorded as distance along
each gallery (in feet) were plotted by fitting a central survey line (with a beginning
measurement and end measurement) along each gallery and geocoding (interpolating) the
specimen data (address/foot) in a manner analogous to geocoding street addresses.
The distribution of the total specimen inventory (all species, and each individual taxon
was examined using a fixed kernel density plot (Figure 2) with a 2m search radius (Bayer,
2004).
RESULTS AND DISCUSSION
The distributions of flint artefacts and of the 13 animal taxa are shown as kernel
density plots with the midpoint of occupied locality “cell” marked as solid circles
(Figures 3a-3d). Although Brixham Cave was entered through a single excavated
entrance (the modern entrance, at the north end of the Reindeer gallery, the entire system
is very shallow and, in the course of the 19th Century excavations, four additional
entrances were excavated from the inside of the cave, out. It is apparent from the kernel
density plot of total specimen distribution (Figure 2) that the modern entrance was not the
point of access for the paleontological materials. It would appear that these remains
entered the cave from the now-sealed entrance into West Chamber, and were distributed
along the Flint Knife Gallery and then north and south along the Reindeer Gallery. Very
few specimens passed through Pen Gallery into the Southern, Kings and/or Keepings’
Galleries, and none into Maunday’s Gallery, the latter at least being sealed with sediment.
Brown bear (Ursus arctos) remains are the most abundant (n=354; Figure 6a) faunal
remains recovered from Brixham Cave, accounting for approximately one half of the total
identifiable recoveries. The spatial distribution of these remains is almost identical to
those of the next most abundant taxon, the reindeer Rangifer tarandus (Figure 5d). Bears
of all ages are represented, including juveniles with milk dentition, with bones of some
individuals found in close association or near-articulation (Pengelly et al., 1873),
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DONALD A. MCFARLANE, JOYCE LUNDBERG and WARREN ROBERTS 4
circumstances consistent with the use of the cave as a den and hibernaculum. Spotted
hyena (Crocuta crocuta; Figure 4c) are the third most abundant taxon in Brixham Cave.
The taxa Bos primigenius, Capreolus capreolus, Cervus elaphus, Coelodonta antiquitatis,
Equus ferus, and Mammuthus primigenius all have similar distributions constrained by
the simple cave layout and were presumably brought into the cave as prey of hyenas. The
cave lion, Panthera leo spelaea, is present in the sparsely fossiliferous Pen Gallery, and
Figure 2. Density map of all 1873 excavated specimens. Points represent the mid-
point of excavated sections. Kernel density plots use a 2m search radius.
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5 A GIS APPROACH TO THE 19TH CENTURY EXCAVATION OF BRIXHAM CAVERN
Figure 3a-3d. Density plots of individual taxa. Points represent the midpoint of excavated
sections. Kernel density plots use a 2m search radius.
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DONALD A. MCFARLANE, JOYCE LUNDBERG and WARREN ROBERTS 6
Figure 4a-4d. Density plots of individual taxa. Points represent the midpoint of excavated
sections. Kernel density plots use a 2m search radius.
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7 A GIS APPROACH TO THE 19TH CENTURY EXCAVATION OF BRIXHAM CAVERN
Figure 5a-5d. Density plots of individual taxa. Points represent the midpoint of excavated
sections. Kernel density plots use a 2m search radius.
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DONALD A. MCFARLANE, JOYCE LUNDBERG and WARREN ROBERTS 8
may be associated with mammoth remains in Southern Chamber which apparently did not
see hyena activity. The artefacts are concentrated close to the West entrance and perhaps
indicate the site of human occupation, with additional material moved into the lower
Reindeer Gallery by sediment flow.
Surprisingly, the Brixham Cave paleontological deposits have never been subjected to
radiometric dating. The main faunal assemblage, which was emplaced below the
stalagmite floor in Pengelly’s ‘Layer 3’, is consistent with the “Pin Hole mammal
assemblage” of Currant and Jacobi (2001). This assemblage is dated to MIS 3 (24 ka – 56 ka; Bassinot et al., 1994). However, the first paleontological specimen to attract notice at
Brixham Cave was a reindeer (Rangifer tarandus) antler that lay above the flowstone
floor; “On a shelving stalagmitic terrace in the interior we saw from a distance a pair of
large Cervine horns horizontally imbedded in the stalagmite;” (Pengelly et al., 1873;
p473). Eventually, excavations would yield 72 ‘determined specimens’ of reindeer, the
majority from “layer 3” below the flowstone floor, but some lying on and partially embedded, in it. If we accept that layer 3 is indeed MIS 3 in age, then the age of the
flowstone floor and its superimposed reindeer are of interest. Stalagmitic deposition was
essentially non-existent in England during MIS 2 (Gascoyne et al., 1983) due to the
prevailing extreme periglacial conditions, so that the flowstone floor was almost certainly deposited during the early Holocene and is probably contemporaneous with the extensive
deposition of the “granular stalagmite” in Kents Cavern, which began approximately
11,000 yrs BP (Lundberg and McFarlane, 2007). Comparable tufaceous flowstone layers
Figure 6a-6b. Density plots of individual taxa and artefacts. Points represent the midpoint of
excavated sections. Kernel density plots use a 2m search radius.
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9 A GIS APPROACH TO THE 19TH CENTURY EXCAVATION OF BRIXHAM CAVERN
of early to mid-Holocene age are known from many other British cave sites, including Broken Cavern and Three Holes Cave, Torbryan Caves (15 kms NNW of Brixham Cave;
Currant 1998), Potter’s Cave, Wales (Davies, 1989), Symond’s Yat East Rockshelter,
Herefordshire (Barton, 1994), Pin Hole Cave, Derbyshire (Jacobi et al., 1998), and Stump
Cross Caverns, Yorkshire (Baker et al., 1996). A Holocene flowstone floor in Brixham
cave requires that reindeer were present in southern England in early Holocene times.
Based on an account in the 13th Century Orkneyinga Saga (Anon., 1200), it has often been argued that reindeer were hunted in Caithness, Scotland, into the Middle Ages. The
evidence has been considered in detail by Clutton-Brock and McGregor (1988), and
shown to be unsupported by modern archaeological evidence. The youngest carbon-dated
reindeer remains from Britain come from Reindeer Cave, Creag nan Uamh, Inchnadamph, Scotland (latitude 58.128 N, 860 kms north of Brixham Cave) dating to
9032 -9478 BP (2σ, SRR1-2105; Clutton-Brock and MacGregor, 1988; recalibrated2 to
Reimer et al., 2004). Specimens from Kitley Shelter Cave, Devon (35kms from Brixham Cave) date to 10,700-11,252 BP (2 σ, Coard and Chamberlain, 1999; recalibrated3 to
Reimer et al., 2004). A newly reported date of 12,329-13,063 BP (2σ ,OxA-180754,
Stevens et al., 2010; calibrated3 to Reimer et al., 2004) from Aveline’s Hole, Mendip
Hills (latitude 51.324 N, longitude 2.753 W, altitude 129 m; 116 kms NNE of Brixham Cave), further demonstrates that reindeer were present in southern England post-Last
Glacial maximum. Steven’s et al. (2010) comment that the great rarity of reindeer in post-
glacial Mendip archaeological deposits poses the question of where Upper Palaeolithic human hunters obtained their prey. The presence of an apparently post-glacial reindeer in
Brixham Cave raises the possibility that the species may have persisted into the Holocene
on the uplands of Dartmoor, some 25kms west of the cave, as first suggested by Coard
and Chamberlain (1999) in the context of the Kitley Shelter Cave specimens.
CONCLUSION
The Brixham Cave excavation was the earliest known archaeological and/or cave site to be excavated according to a protocol that preserved the spatial relationships of the
materials. The 19th century spatial data is robust enough that it can be readily entered into
a geographic information system format for display and analysis.
Basic analysis suggests that the paleontological remains primarily result from the
activities of three taxa; brown bears using the cave as a hibernaculum, and hyenas and
cave lion using the cave as a den, both accessing the cave from the western entrance in MIS 3 time. The origin of the apparent Holocene Rangifer antler, located at a point in the
Reindeer Gallery remote from the western entrance is more obscure; it is unlikely that the
modern (north) entrance was ever open in Holocene time prior to its excavation in 1858.
ACKNOWLEDGEMENTS
We thank the current owners of Brixham Cave, Mark and Beverly Langley, for their support. This work was supported in part by a research grant to DAM from Scripps
College.
1 NERC radiocarbon Laboratory, East Kilbride, Scotland.
2 http://calib.qub.ac.uk/calib/calib.html
3 http://calib.qub.ac.uk/calib/calib.html
4 Oxford University Radiocarbon Unit.
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DONALD A. MCFARLANE, JOYCE LUNDBERG and WARREN ROBERTS 10
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