Chain and Cable Test House and Store, Capstan, Chain Haulage-Ways on North (Building Number 1/41)

This is a naval chain and cable test house and store, with a capstan and chain haulage-way on the north side. It was built between 1844 and 1847 by Captain RS Beatson (Royal Engineers), with roof work by H Grissell. An annealing house was added in 1866, and the building was extended between 1879 and 1880 to accommodate more powerful testing machinery. It suffered bomb damage in 1940, leading to later rebuilding of the external structure, and the floor was relaid between 1991 and 1992.

The building is constructed of red and brown brick in Flemish bond, with later 20th-century additions in pink brick using English and stretcher bonds. The roof is corrugated metal with long roof lights. It is a large, single-storey rectangular structure comprising several parallel-roofed ranges set at right angles to each other. Original circular iron windows are interspersed with small-pane metal windows, featuring segmental brick arches, stone lintels, or 20th-century concrete lintels and sills. Sliding board doors are also present, similarly arched and lintelled. On the west side, a principal range (likely dating from 1879/80 and featuring 20th-century repairs) has nine bays arranged 2:2:1:2:2, with a central door flanked by paired windows, and further paired windows at each end, flanked by broad brick pilasters which rise into stepped brick eaves. The 13-bay north side range on the right has three doors. From the left-hand door and the door of the range on the left, granite setts form haulage-ways that run out of the building towards a waisted turning bollard.

Inside, the building has a cast-iron frame consisting of two aisles of Tuscan columns on plinths, supporting I-section beams and tied at three-quarter height by segmental-arched ties with moulded spandrels. The roof is supported by trusses with paired wrought-iron ties and decorative cast-iron struts. The floor is laid with wooden blocks and granite setts, incorporating iron ballast castings with an arrowhead design and the letters "PO", indicating the Portsmouth Dockyard. There are also turning bollards (formerly operated by two capstans), and an inspection pit.

This building served as the first testing and storage facility for iron cables introduced into the navy from the 1830s. It originally contained chain storage, an eastern testing house, a northern junk (worn cable) store, a southern painting shop, and a chain cleaning shop, along with an annealing furnace. The iron ballast castings were marked with the Portsmouth Dockyard identification, allowing commercial dockyards undertaking refitting to know where to return the ballast. The building represents a remarkable survival, showcasing fireproof design and its unique purpose. Captain Beatson was also responsible for the Fire Stations and No.6 Boat Store at Portsmouth.