to protect newly manufactured anchor chain. The roof is supported by a row of 28 captured French and Spanish guns. Surviving structures within the Victorian Steam Yard The Victorian Steam Yard was built around three large Basins (wet docks), constructed between 1865 and 1885 along the line of St Mary's Creek (separating St Mary's Island from the mainland). It was envisaged that Basin No 1 would serve as a "repair basin", No 2 as the "factory basin" and No 3 as the "fitting-out" basin; a newly launched ship could therefore enter via the west lock, have any defects remedied in the first basin, have her steam engines and heavy machinery installed in the second, and then be finished, and loaded with coal and provisions, in the third before leaving via the east locks. Four drydocks (Nos 5–8) were constructed at the same time on the south side of No 1 Basin; all four were in use by 1873. The yard's Steam Factory complex was built at around the same time; most of its buildings were sited around these docks (rather than by Basin No 2 as had originally been planned). No 1 Boiler Shop and No 8 Machine Shop were originally built as slip covers at Woolwich Dockyard in the 1840s. When that Dockyard closed in 1869 they were dismantled and rebuilt at Chatham alongside the new dry docks. Only the framework survives of the Machine Shop, but the Boiler Shop was renovated in 2003 to house the Dockyard Outlet shopping centre. A third such structure from Woolwich, similar in design to the boiler shop, stood nearby and served as a fitting shop; it was demolished in 1990. Dock Pumping Station 1874: as well as serving to empty dry docks 5–8 when required, its accumulator tower provided hydraulic power for the adjacent cranes, capstans and caissons. Two other pumping stations served a similar purpose (one for dock 9 and one for the two east locks) but they have not survived. Combined Ship Trade Office 1880: now the "Ship & Trades" public house. A fifth dry dock (No 9) was added in 1895 on the north side of No 1 Basin, opposite the other four, to accommodate the new, larger battleships which were then under construction. It was completed in 1903. The 100 ft bell mast was erected in 1903 alongside the Dockyard's Pembroke Gate, where it was used to signal