Summarised from report:

A substantial rampart rises from above the scarp revetment, composed of redeposited soil and chalk carefully scarped into a steep even slope to absorb incoming fire. Beyond the crown of the rampart, lies the terreplein where the greater part of the artillery was to be mounted. The broad rampart extends around the north, east and west faces, with an infantry parapet closing off the gorge above the cross ditch. The terreplein supports four gun emplacements, each with a ready-use shell recess, while an expense magazine and an artillery store are contained in bombproof traverses. Captain Du Cane’s terreplein of the 1860s had emplacements for ten guns, firing through embrasures in the rampart, and was interrupted by traverses over the magazine, artillery store and gallery entrances. The 1890s alterations concealed this original arrangement by thickening of the rampart on the inside and infilling of the original embrasures, although the traverses were retained in a shortened form. An earthwork ramp up to the terreplein on the west side is also of the 1890s. There are four identical gun emplacements, each emplacement is made in concrete with a vertical front wall forming a barbette 1.35m high and 0.6m thick, with flank walls ramped down and splaying to the rear, and a level gun floor. The floors each incorporate two steel racer arcs for guns mounted on traversing platforms with ‘C ‘ pivots, enabling a theoretical 70º arc of fire. All are in the locations proposed in 1889 and follow a common design, let into the talus for protection, at the end of short passages with concrete side walls (where not built against an existing structure) that are ramped down to the rear. (1)

A plan dating to 1810 shows the Detached bastion as it was originally constructed and before any improvements were made under the 1860's scheme of works, (2) while another dating to 1862 shows the bastion after the major improvements have been made and includes details of the gun emplacements and some of the interior structures. (3) A further plan dating to 1889 shows the planned alterations to the gun emplacements, reducing their number from 10 to 4. (4)

<1> RCHME, 2001, The Western Heights, Dover, Kent. Report No 7: North Centre and Detached Bastions: 19th-century fortifications (Unpublished document). SKE17503.

<2> E B Metcalf, Royal Military Surveyor and Draughtsman, 1810, Kent: Dover. Map showing fortifications. At the Western Heights
Kent: Dover. Map showing fortifications. (Map). SKE51587.

<3> Office of Works, 1862, Plan showing the improvements to the defences for Dover at the North Centre Bastion at the Western Heights (Plan). SKE51590.

<4> Royal Engineers, 1889, Plan of the proposed reconstruction of a parapet for the reception of four 7inch guns at the Detached Bastion (Plan). SKE51591.