ABSTRACT
The march of improvement in the blast furnace has been characterized particularly in Britain and the United States by a great increase of dimensions, which is found to promote economy in fuel. The proportions of fuel, ore, and limestone charged into the furnace vary greatly according to the composition of the ore, the quality of iron aimed at, and the practice of each manufacturer. Meteoric iron is too rare to be of any value as a source of iron, but certain specimens have been found in which the metal was malleable and of excellent quality. The nature and value of what has been done during the century in the treatment of iron would not be intelligible without some description of the ordinary processes of extracting the metal from the ores. Only the best and most refractory materials, such as firebricks, are used for the lining, and the exterior is a casing of solid masonry, strengthened with iron bands.
