Rope House has spinning on the upper floors and ropemaking (a ropewalk) on the ground floor. It is long, and when constructed was the longest brick-built building in Europe capable of laying a rope. Over 200 men were required before 1836, to make and lay a 20in (circumference) cable. All was done by hand. Steam power in the form of a beam engine was introduced in 1836, and then electricity in the early 1900s. The White Yarn House to store the yarn before it was tarred to prevent rot. The Tarring House with its "Tar Kettle" and horse drawn winch. The Black Yarn House to store the tarred yarn. The tarring process declined as manila replaced hemp, and sisal replaced manila. These fibres were chemically protected at the hatchelling stage and tarring stopped in the 1940s. Metalwork No 1 Smithery 1808. Originally consisting of three ranges around an open courtyard, it was designed by Edward Holl and fitted out by John Rennie with 40 forges for production of Anchors and Chain. Anchors could weigh , and were forged by hand. "Anchorsmiths" were given an allowance of of strong beer a day, because of the difficult working conditions. In 1841 a beam engine was installed (in an extension to the north-east) to replace the manual bellows; another was added the following year. The courtyard was roofed over for a steam hammer shop in 1865. Lead and Paint Mill 1818. Designed by Edward Holl to be fireproof. There were a lead furnace, casting area and steam powered double rolling mill, paint mills for grinding pigment, canvas stretching frames, and vats for storing and boiling linseed oil. A warship was painted every 4 months. Iron Foundry 1855–61. Built immediately to the north of the Smithery (the intervening space was later infilled with the Smithery extension of 1867). Extended in connection with preparations for HMS Achilles (see below). No 1 Machine Shop 1861. This building retains it original structure and roof glazing. It was used to house the machine tools needed to produce HMS Achilles, the first iron battleship built in a Royal Dockyard. This building has now become home to the railway workshop. The Galvanising Shop . Galvanising is a process of dipping steel in molten zinc to prevent it from rusting. There were baths of acid and molten zinc, the fumes vented through louvres in the roof. Chain Cable Shed , built