some time ago, specially in search of a material suitable for making castings, which should possess hardness and toughness, the principal reason for this being that ordinary steel castings do not combine these qualities. Cast-steel, unlike cast-iron, cannot be chilled " ; this is a great disadvantage, for although steel castings of ordinary tempers may be exceedingly tough, as soon as any degree of hardness more or less is reached, by an addition of carbon or other bodies, the toughness rapidly decreases, the material becomes brittle, and in any case does not possess the intense hardness of chilled-iron. Even steel cast with more than 2 per cent. of carbon is comparatively soft ; and whilst chilled-iron cylinders, 0.79 inch in diameter by 1 inch long, remain unaltered under a compression-load of 100 tons per square inch, cast or forged-steel cylinders of all kinds in the natural state, that is, unhardened, shorten from 15 to 40 per cent. according to temper. Suppose, for example, that molten steel of any temper, as hitherto made, is run into an iron mould used for making " chilled rolls," when cold the grain of the casting will be somewhat closer than if cast in sand, but still quite soft, easily indented, and may be turned in ordinary lathes. The same article made from cast-iron of suitable mixtures would be intensely hard or chilled on the surface, whilst the necks and tenors cast in sand would be quite soft. Here then is a drawback to the use of cast-steel, as, although it may be