Royal Arsenal Brass Foundry Royal Foundry

Brass cannon foundry, now book store. Built 1716–17, possibly by Sir John Vanbrugh, for the Board of Ordnance; extended and altered 1771–1774 by Jan Verbruggen, Master Founder; extensively repaired in the 1970s and converted to book store use.

The building is constructed of dark red brick with red rubbed brick and stone dressings beneath slate roofs (originally tiled). It follows a symmetrical plan of a central founding range with lower side aisles and a north entrance tower with flanking blocks.

The exterior rises to 2 storeys and attic. The central 3-bay tower has clasping pilasters on stone plinths and a fine entrance with pilasters of alternating rubbed brick and stone supporting a forward-set cornice. The doorway is round-arched with rusticated voussoirs and the Duke of Marlborough's Arms carved at the key, a radial fanlight and double doors with 10 raised panels. Rubbed brick round arches with keys and imposts frame 19th-century casements on either side; above these are segmental-arched blind panels, and first-floor round-arched windows flank a wide 3-centred arched panel above the doorway bearing a fine coat of arms of George I. The 3-bay sides feature round-arched first-floor windows. The pyramidal roof carries 2 pedimented dormers to the front and a round lead-clad cupola (added 1722) with architraves to small-paned windows, angle buttresses and a domed roof with finial.

The single-storey side aisles have round-arched windows linked by an impost band and a 3-centred-arched doorway (originally a central porch). The rear section is a 2-storey former furnace block, possibly raised in the 1770s, built of contrasting paler brick with clasping pilasters and window surrounds; it has round-arched ground-floor and segmental-arched first-floor windows. The west side has a matching 2-storey rear block, but the section to the north was rebuilt around 1878 as single-storey with blind windows. The south end has a 2-storey block with chamfered corners and parapet, possibly dating from 1803. The founding range features continuous clerestory windows beneath the eaves and louvred ridge vents.

The interior contains an entrance hall with cast-iron plates fixed to the inner wall; the uppermost is inscribed "TRANSFERRED TO ROYAL LABORATORY 1878", and another round-arched plate bears the inscription "177?/VERBRUGGEN/J KING/H KING/1771 SCHALCH/KING/NORTH/ECCLES/1855". A 19th-century iron spiral staircase leads to the tower, which has a heavy timber roof. The flanking ground-floor bays have round arches to the south walls with imposts. The central founding range behind features a 9-bay king post roof with butt purlins and ridge vents; the 2 northern trusses are closed off, and the south end has a mid- to late 19th-century metal-trussed roof with blind round arches to the sides. The east aisle has a steep roof with collar trusses, tie beams, butt purlins and a ridge board, with a cast-iron beam bolted to the west wall plate.

The foundry was built as part of the initial expansion of the Royal Arsenal following the Board of Ordnance's establishment of its own foundry at Woolwich. It was designed to cast brass cannon and laid out on an axis facing the river. The furnaces occupied the 2-storey rear ranges, with casting pits between and a gallery and windlass above; model and pattern-making took place to the north, and a large balance was positioned inside the main entrance. Open arcades along the sides of the founding range (now blocked) connected these spaces. The heavy roof, much of it original, served a structural purpose in lifting operations, and a vertical cannon-boring machine may have been housed in the tower. Verbruggen's alterations and extensions of 1771–74 accommodated a third foundry, although advances in casting and boring of iron were by then making brass cannon obsolete. Steam boring equipment replaced horse-powered mills in 1827 and 1842.

The building is of considerable historic significance as a rare, early and little-altered example of a purpose-built foundry and workshop, substantially reworked at the beginning of the industrial revolution.