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"A very powerful and economical one, for large establishments especially. It is a modification of the well-known Cornish boiler, and consists of two wrought-iron cylinders substantially rivetted together, and having a water space of about 2 inches between them. The frame for the furnace doors d is attached to the front. It is supported by two cast-iron chairs a, a, the front chair forming the frame for the lower flue doors b, which fasten by a simple catch, and can readily be lifted off for cleaning the flues. The plug c, opened by unscrewing it, is for the purpose of clearing out all interior accumulation of dirt, which should be done thoroughly at short intervals. The flow pipe is at e, the return at f." — Encyclopedia Britannica, 1893

Trentham Boiler

"A very powerful and economical one, for large establishments especially. It is a modification of the…