18 June 2015

Scarlett Chain Home, Isle of Man

The first network of early warning radar stations built around the coast of Britain before and during WWII was code-named Chain Home (CH). Two stations were built on the Isle of Man, at Bride in the north and Scarlett in the south, near Castletown, and were online by September 1940.

Operated by the RAF, as all CH stations were, the IoM facilities were designated as Advance Chain Home stations, brought online with temporary short timber masts supporting the transmitter arrays, in advance of the availability of 325-foot guyed steel masts. CH Bride closed in 1942, as it duplicated an area already covered by stations in Scotland and Ireland. CH Scarlett closed the same year, as it was too close to Ronaldsway airport and the fleet air arm training unit, HMS Urley, based there. 

Scarlett was replaced by a new CH station at Dalby, on the western side of the island, which operated for the remainder of the war. Scarlett CH had two Type B operations blocks, without protected roofs, each with two sets of equipment; and two Type C blocks, covered with earth, each with one set of equipment. All four blocks remain, in farm use.

17 June 2015

In the Glasshouse

The World of Glass Museum in St Helens, which incorporates the Pilkington Glass Museum, is home to the remains of the oldest surviving gas-fired continuous-tank glass furnace in Europe. The furnace is contained within the Grade II*-listed No.9 Tank House, itself part of Pilkington's Jubilee Glassworks, built next to the Sankey Canal.

The tank house, known locally as the Hotties, boasts a truncated conical flue that once rose above the Siemens regenerative furnace below, installed by Pilkington's in 1889 and in use until 1920. The materials to make glass were fed on a continuous basis into a brick-lined tank and melted together, to provide an endless stream of molten glass. A throat part-way along the tank filtered out impurities. The molten glass was blown into cylinders eight feet long, which were cut open, flattened and polished to produce window glass.

Heat derived from burning coal-gas, used to melt together the raw materials, was recirculated beneath the tank, through a series of flues filled with a latticework of refractory bricks, to keep the molten glass workable. These flues, and the swing chambers in which the cylinders were formed under the influence of gravity, could be accessed by brick-arched service tunnels.