FAVERSHAM TR 06 SW HAM ROAD 659/6/10021 East Crystallising House (Building 11) 14-DEC-01 at former Marsh Gunpowder Works, Work shop Area GV II Crystallising house at saltpetre refinery, part of gunpowder works, now store. 1789. Timber framed, clad with weatherboard, with corrugated iron hipped roof. PLAN: Long narrow plan. EXTERIOR: Single storey, now open to NE side (morticing for former louvres clearly visible), 12 bays long with strutted timber posts, covered to the ends and rear with louvred openings and a central doorway. INTERIOR: Strutted king posts ties, corner ties, and matchboard lining to roof. HISTORY: The Marsh works were part of the Royal Gunpowder Factory which was established outside Faversham in 1786 after an explosion in the town, to remove some of the more dangerous processes. They played an important part in the improvement of the British gunpowder leading up to and during the Napoleonic Wars, under William Congreve. The saltpetre refinery which was built 1789 as part of Congreve's successful drive to improve the ingredients of British powder. It was privatised after the war, and closed in the 1920s. The crystallising house was where saltpetre was crystallised out of the solution which had been treated in the nearby refining house (qv), by placing it in racks of vats to cool, hence the open structure. It is the best preserved building on this historically important site, and survives as a particularly impressive example of a late C18 industrial building through the close relationship between the structure and the process. It forms part of a discrete, coherent group of late C18-early C19 industrial buildings for refining saltpetre, the best preserved of this type in the country comparable with French and Swedish examples. (Wayne Cocroft, Dangerous Energy. The archaeology of gunpowder and military explosives manufacture. Swindon (English Heritage), 2000, pp. 54-67)