Monument MPM1920 - Blacksmiths Shop, Gunwharf

Three structures associated with a former blacksmiths shop at Gunwharf were observed during a watching brief in 2002. These were interpreted as two casting pits and the outer north wall of the shop. The base of a large machine was also recorded.

Three structures associated with a former blacksmiths shop at Gunwharf were observed during a watching brief in 2002. These comprised the remains of two casting pits and the north wall of the shop. The base of a large machine, possibly a steam hammer or hydraulic press, was found next to the latter.

The blacksmiths shop was built in 1805 and replaced an earlier smiths shop shown on a plan of 1799. It originally consisted of a foundry, mould shop and pattern store, blacksmiths' shop, platers' shop, pattern shop, machine shop and grinders' shop. The building had been extended by 1862 to accommodate additional workshops. By the start of the Second World War the building was in use as the Mine Design Department Workshops. The shop was badly damaged during air raids in March 1941 and demolished 1945/6.

Casting pits
The remains of two structures were interpreted as casting pits due to their depth and construction. One structure was situated within the footprint of the main shop. The second, to the west, was outside the footprint of the shop but was thought to have been associated with it as it was of similar construction.

The pits were rectangular in shape with brick walls approximately 6m wide by 3-4m in length. The walls had been constructed using two-skins of bricks separated by vertical ceramic peg tiles in a hard white lime mortar. The base of one of the structures was observed in section and consisted of a stone flagged foundation slab with a two-skin brick floor separated by peg tiles. This unusual method of construction using peg tiles between two-skins of brick has been found elsewhere in Portsmouth and was used to form a barrier to prevent water from entering. Only the walls below the water table were observed and it was thought that they were unlikely to have formed supporting walls to the structure above ground.

Outer Wall
A structure, consisting of three different elements joined by a series of brick walls, was situated within the later Foundry and Boiler room. This was interpreted as the outer north wall of the shop. The base of a large machine with a cemented cube foundation was observed next to the structure. Due to its size this was thought to have possibly belonged to a steam hammer or hydraulic press.

Barge, Melanie, 2002, Canalside Blocks Gunwharf Portsmouth: Report on the Archaeological Watching Brief (Unpublished document). SPM519.