Details

The monument includes a large gun battery situated behind the southern crest
of the summit plateau of The Garrison, the south western promontory of St
Mary's in the Isles of Scilly. The battery is one of two complementary gun
batteries, with a barracks/caretakers quarters between them, built on The
Garrison between 1898 and 1901 and forming part of a defensive system designed
to protect a naval signalling and re-fuelling station then being established
on the Isles of Scilly. The defences were operational until 1906 but the
monument also includes minor structures from reuse of the site during World
War II. The built and earthwork structures in this monument are also Listed
Grade II. The listing extends to include the built structures of the battery's
underground magazine and war shelter which are excluded from this scheduling,
although the ground beneath and above is included.
The battery's forward flank faces SSW, its field of fire commanding the deep
water approach to the islands through St Mary's Sound. It has two concrete
emplacements for 6-inch breech-loading (BL) MK VII calibre guns set into the
rear of a rampart, behind which is a parade area called a terreplein. Beneath
the emplacements are an underground brick-vaulted magazine and war shelter
reached by a concrete-faced light-well. The terreplein contains a raised
platform, called a traverse, containing a communications room and supporting
the Battery Commander's Position and range-finding post. The emplacements,
terreplein and magazine are contained within substantial earthwork defences
comprising a forward rampart and a fully encircling outer ditch.
The concrete gun emplacements are situated 25m apart in the rear of the
rampart. Each emplacement includes a raised podium around a circular central
recess which housed the central-pivot gun mounting. On its forward side, the
podium merges into the wider, slightly higher, rear face of a broad concrete
apron whose gently chamfered surface extends over the adjoining rampart top.
The rear faces of the podium have cast-in metal brackets for handrail
stanchions and contain recessed lockers to house shells and cartridges
required for immediate use; the metal handrails and locker doors have not
survived. Further lockers occur beside the podium in the adjoining rear face
of the apron; shell and cartridge lifts from the underground magazine open at
hatches in the rampart's concrete facing to each side of the podium. A
concrete terrace extends back from the podium, ending at a sloping scarp down
to the terreplein with access steps at each side. Beside the inner flank of
each emplacement, concrete steps rise from the terreplein to the rampart
crest. A flagstaff left of the ESE emplacement indicated when live firing was
taking place.
Between the emplacements is a deep rectangular lightwell, partly recessed into
the rampart rear, with steps descending from each end to the battery's complex
of underground structures which form that part of the Listed Building excluded
from this scheduling. These comprise a brick-vaulted magazine with two
cartridge stores and three shell stores, and a war shelter. These structures
retain their original plan, though most original internal fittings, doors and
joinery have been removed from areas still accessible. The SSW wall of the
lightwell bears a concrete date-slab inscribed `1900'.
Behind the emplacements and lightwell is the rectangular levelled terreplein,
c.55m long, extending c.15m back from the rear of the rampart and defined to
the sides and rear by a wall. Behind the lightwell it is paved to waterproof
the underground structures beneath and drains led out beneath the outer
defences from each end of the terreplein. The battery entrance is near the
eastern end of the terreplein rear, now visible as an open gap but formerly
closed by double armoured steel gates with loopholes. The gates opened
outwards, borne on rollers engaged in surviving curved rails.
Within the terreplein, the concrete-revetted semicircular traverse extends
from the centre of the rear wall; it contains a small communications room
accessed from behind the traverse. The traverse platform supports a concrete
parapet covering the Battery Commander's Position. Above the communications
room and parapet is a slender concrete post which formerly supported Watkin's
depression range-finder (DRF) sighting equipment. The DRF at this monument was
calibrated by sighting onto a datum post on the Cow Rock north of St Agnes.
Close to the east of the DRF post, a small raised concrete structure contains
a recessed locker in its rear face to house charts and an electric telegraph
for recording and transmitting DRF data to the gunners. In the south west
corner of the terreplein, against the rampart rear, is a small latrine.
The battery's emplacements, magazine and terreplein structures are built
within extensive low profile earthworks to protect them from incoming fire and
ground approach. The earthworks include a forward rampart which, with the
battery's other structures, is contained within a subrectangular ditch. The
rampart reaches its crest between the gun emplacements, from where it slopes
gently down, extending the profile of the natural slope beyond the ditch.
Where it meets the ditch, the rampart measures 65m WNW-ESE by up to 21m wide
and rises to 3m above the parade level at the gun emplacements. The broad
subrectangular ditch extends around the outer edges of the rampart and the
sides and rear of the terreplein to protect all of the battery's operational
structures from ground approach. The ditch is flat-bottomed, 7.3m wide at the
base, ranges from 15m-25m wide at the lip and measures 108m WNW-ESE by up to
78m NNE-SSW externally. It is interrupted only at the north east corner, at
the entrance, and was designed to be filled with barbed wire entanglements
secured by retaining spikes. The low profile of its earthworks rendered the
battery more difficult to locate and target for enemy gunners and masked both
ditch and emplacements from external view while allowing an unobstructed and
wide field of fire for the guns.
The Garrison's commanding position made it the focus for successive phases of
fortification on Scilly from the later 16th century. In the 1890s, a joint
army and navy review of the nation's coastal defences proposed the Isles of
Scilly should become an advanced naval signalling and re-fuelling station, to
be classed as a defended port, in view of their strategic position against
perceived threats from French Atlantic naval bases. Implementation of these
proposals between 1898 and 1901 produced two complementary gun batteries, this
monument and the Steval Battery 125m to the north west, to cover the deep
water approach to the islands and served by a barracks/caretaker's block
between them. Records indicate that the batteries' magazines held 500 rounds
per gun. The battery and the barracks defences reflect the latest
fortification designs and technology available at the time.
By 1902, the 6-inch guns of these batteries were felt to give inadequate
defence against motor torpedo boat attack; a proposed third 6-inch gun battery
was abandoned in favour of two 12-pounder quick-firing gun batteries, one
above Steval Point, 275m north west of this monument, the other at Bant's Carn
on the north western coast of St Mary's. Other structures of the defensive
system in which this monument operated include coastal searchlight
emplacements and their control posts at Woolpack and Steval Points, with their
electricity supply generator housed in an 18th century battery between them.
An artificer's workshop for the maintenance of the batteries' guns and
mountings survives near the summit of The Garrison, 140m north east of this
monument.
During construction of these defences, national defence policy underwent a
radical shift. German power replaced that of France as the dominant threat, a
re-orientation strengthened by the signing of the Entente Cordiale in 1904. In
the resulting re-alignment of the nation's defences to the east, detailed in
the Owen Report of 1905, the Isles of Scilly were abandoned as a naval station
and, with little commercial importance, they also lost their defended port
status. Consequently, though these batteries had been used for coastal defence
training, their guns were dismantled in 1906 and by 1910 had been removed for
storage in Falmouth.
During World War II, The Garrison housed a radar cell and aviation fuel
stores. A homing beacon was installed on the Woolpack Battery to guide anti-
submarine aircraft returning from patrol to airfields in south west England.
It is in this regard that two raised concrete mast bases were added, one on
each apron of the emplacements. Each mast base is visible as a raised cross
with an enlarged square centre and transverse terminals. The beacon was
powered by electricity generated initially by two Ford engines in the
battery's underground complex, later replaced by mains cables brought to the
battery. One of the magazine's cartridge or shell stores was also used as a
barracks for Royal Canadian Air Force personnel. The battery's underground
complex was also used to store aviation spirit after bombing raids in 1940
threatened its former location on Hughtown Pier.
The battery's undergound complex, comprising its magazine, war shelter and
lockers, are excluded from the scheduling but the ground beneath and above
them is included. All modern signs, fittings, service trenches and their
contents, and dumped debris are excluded from the scheduling but the ground
beneath them is included.

MAP EXTRACT
The site of the monument is shown on the attached map extract.

Source: Historic England

Reasons for Scheduling

The Isles of Scilly, the westernmost of the granite masses of south west
England, contain a remarkable abundance and variety of archaeological remains
from over 4000 years of human activity. The remote physical setting of the
islands, over 40km beyond the mainland in the approaches to the English
Channel, has lent a distinctive character to those remains, producing many
unusual features important for our broader understanding of the social
development of early communities.
Throughout the human occupation there has been a gradual submergence of the
islands' land area, providing a stimulus to change in the environment and its
exploitation. This process has produced evidence for responses to such change
against an independent time-scale, promoting integrated studies of
archaeological, environmental and linguistic aspects of the islands'
settlement.
The islands' archaeological remains demonstrate clearly the gradually
expanding size and range of contacts of their communities. By the post-
medieval period (from AD 1540), the islands occupied a nationally strategic
location, resulting in an important concentration of defensive works
reflecting the development of fortification methods and technology from the
mid 16th to the 20th centuries. An important and unusual range of post-
medieval monuments also reflects the islands' position as a formidable hazard
for the nation's shipping in the western approaches.
The exceptional preservation of the archaeological remains on the islands has
long been recognised, producing an unusually full and detailed body of
documentation, including several recent surveys.

The distinctive form of gun batteries developed at the end of the 19th century
differed fundamentally from earlier batteries and provided the first
application of principles that came to dominate the design of such defences in
the 20th century.
Their design and location reflects major developments in armament technology,
strategic thought, the nature of the perceived threat and defensive policy. By
the mid 1880s the development of an effective breech-loading system had
considerably improved the speed of re-loading guns. Hydraulic and compressed
air systems enabled the recoil of guns to be absorbed, allowing guns to be
located on fixed centrally pivoted mountings which improved accuracy and speed
of firing. Hydraulics were also deployed for ammunition supply from magazines.
Lighter steel barrels and improved propellants gave greater muzzle velocities
and range without requiring corresponding increases in gun size and weight,
thereby increasing the manoeuvrability of the guns while the deployment of
brass cartridge cases further increased the speed of re-loading. The invention
of smokeless powder reduced the visibility of guns on firing. Coupled with
these advances, the development of new range-finding equipment and electrical
communications considerably increased the speed and accuracy of target
position finding and the control and coordination of armament. These
technological changes revolutionised the nature of field fortification
considered appropriate to house the guns. Priority was given to open
emplacements with fixed gun mountings and low profile earthwork fortifications
which were hard to target while allowing the guns maximum manoeuvrability;
defence against close quarters ground approach was provided by the newly-
developed barbed wire entanglements in concealed ditches, reinforced by
machine-gun and rifle fire across the unobstructed ramparts.
The gun emplacements were served by underground magazines with hydraulic
hoists. Early applications of these new principles of fortification were made
in the later 1880s in the rather different context of infantry reboubts in
south east England, their form characterised as the `Twydall Profile'. During
the 1890s variants and developments of the Twydall Profile dominated new land
fortifications for infantry and artillery, providing a major influence on the
design of the defences constructed on the Isles of Scilly during its 1898-1906
phase of fortification.

The Woolpack Battery has survived well, preserving the original plan of both
its earthwork and built structures with only very minor modification from
reuse during World War II. Such intact survival of a battery from this phase
is rare and of much importance for our knowledge of the development of modern
artillery defences. Most other components in The Garrison's contemporary
defensive system, which included this battery as a major integral part survive
well. Spatially, the rare survival of such a complete defensive system allows
the relationships of its components to be studied against their armament
capabilities and the strategic methods by which those defences were intended
to be used, in the controlled background of a single location. The system of
defences to which this monument contributed was directly inspired by
considerations of national defence; as such it also has a wider historical
importance whose immediate context is defined by the national defence reviews
which led to the implementation and later the abandonment of the naval base
which this battery was designed to protect.

Source: Historic England

Sources

Books and journals
Saunders, A D, Fortress Britain, (1989)
Saunders, A D, Fortress Britain, (1989)
Stevenson, I V, Some West Country Defences, (1989), 11-26
Other
1901-2; now in Public Record Office, Edwards, H, Measured plans and sections made on completion of battery, (1901)
Entry 1358-0/3/89, DNH, List of Buildings of Special Architectural or Historic Interest, (1992)
Entry 1358-0/3/89, DNH, List of Buildings of Special Architectural or Historic Interest, (1992)
Information given to MPPA by phone from Dick Linzey, 1/9/1995,
Keystone Historic Buildings Consultants, Star Castle, St Mary's, Isles of Scilly, 1993, Unpublished report for EH
Letter dated 3/11/1993, J Guy, Fortress Study Group, Letter to J Ratcliffe, CAU, re Scilly defences 1902-1910, (1993)
Letter dated 3/11/1993, J Guy, Fortress Study Group, Letter to J Ratcliffe, CAU, re Scilly defences, 1902-1910, (1993)
Notes ref to J P Osborne's diaries, Parkes, C/CAU, Scilly SMR entry for PRN 7908.06, (1994)
Parkes, C/CAU, Scilly SMR entry for PRN 7903.07, (1994)
Parkes, C/CAU, Scilly SMR entry for PRN 7908, (1994)
Parkes, C/CAU, Scilly SMR entry for PRN 7908.06, (1994)
Parkes, C/CAU, Scilly SMR entry for PRN 7909, (1994)
Report for Cons SW, Feb 1994, Linzey, R and EH Architecture Branch, Recs for Incr Statutory Protectn to Woolpack & Steval Batteries, Cons SW, (1994)
Title: 1:25000 Ordnance Survey Outdoor Leisure Map, No. 25: Isles of Scilly
Source Date: 1982
Author:
Publisher:
Surveyor:

Source: Historic England