machine was of the spade type pushed by hand but there was a set of tongs on a monorail for lifting the full pots from the furnaces and teeming. They can teem 4 to 6 pots per hour. There was one large casting table and rollers, the table being about 6 metres long by 4 metres wide. This was not water cooled, nor was the roller. The thick plates from this larger table were annealed in one or other of several single-plate kilns. Plates were pushed into kilns or the lehr by hand. It was stated that they could cast up to 30 mm substance on this table.
There were also two small Chance type rolling machines with narrow tables about 4 ft. wide which could be pushed in front of a roller lehr about 80 yds. long, wide enough to take the plates with the table length as the width of the lehr. It was stated that the rollers in this lehr were asbestos covered, but at the cold end they were wooden. This lehr needs repairing.
Founding cycles were stated to vary from 24 to 36 hours. With the plant being out of action, no personnel were available to give reliable details of cycles for particular glasses.
Pots average 30 founds when used for casting and sometimes 50 founds for blowing work. Pots are stored in a heated chamber near the arches before arching. Pot arches are top-fired, the flames passing over the pots (2 small pots or 1 large in an arch) and down the far side, the products of combustion returning across the arch beneath the bottom tiles.
At all furnaces and pot arche3 (which were gas fired) the gas, air and draught controls were neatly arranged in panels near their respective furnaces, with height measuring arrows, and warning bell pushes to the producers for gas quality and quantity variations; there was no automatic regulating device for gas pressure. The gas valves were of the old revolving drum type and the air valves were the butterfly kind.
3. Glasshouse Pots
The pots were made from a Grossalmerode clay mixture by the traditional German beating method.
Two clays from Grossalmerode were used and were said to be of the same composition, namely 22 per cent alumina content. They were mixed dry with 25 per cent of Steinberg-Bocksgraber grog and 25 per cent of potsherds. The grading of the grog was as follows:-
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