Page:The Working and Management of an English Railway.djvu/138

 latter travel along the shop, wherever they are required, at the rate of 80 feet per minute, and lift their loads at the rate of 9 feet per minute. Special light machinery of a similar type has been provided also in the erecting shop, and in the various repairing shops, and is found almost invaluable in facilitating the operations to be carried on.

One portion of the works which seldom fails to interest visitors is the steel works, which, at the time of their opening in 1864, consisted of a converting house with two converters, a cogging shop, and a small forge, but have since been greatly enlarged, the steel-making plant being now capable of producing 50,000 tons of steel per annum, besides which there have been added a large forge, iron, brass and steel foundries, rail- rolling mills, a boiler shop, and several repairing and other shops. To those who are not acquainted with the Bessemer process of converting iron into steel, a brief description of the operation may be interesting

The converting plant consists of four retorts or vessels, each holding 5 tons, and arranged in two groups, with the cupolas behind them. The pig-iron is first melted in a cupola, to which the air is supplied by a Root's blower, after which the liquid metal is run into a huge ladle moving on a line of rails, and is conveyed to the converting vessel. This latter is lined with ganister, and in the bottom of it are a number of small holes, through which air is injected upwards through the molten mass, the oxygen of the air combining with and eliminating the carbon of the iron, and keeping up a fierce combustion until the whole of the impurities are ejected. The blowing is continued for some fifteen