involved in the Construction of A rtillery. 243 



basis of Herr Kruppe's patent process, the steel, however, being primarily 

 obtained by a regulated and skilful puddling, stopped at the proper moment, 

 by which he has been enabled to form masses of unusual magnitude, and to 

 manufacture articles of various sorts previously not attainable in steel, such as 

 tyres for railway wheels, formed of one piece without welding. This steel 

 presents no trace of fibre, its fracture seems the same in every direction, and 

 its crystals are so minute that the lustrous surface of fracture on a large scale 

 seems almost a vitreous one. As for size, he has pushed his manufacture to 

 a point leaving nothing to desire, and it is capable of still greater extension. 

 The price of the material, however, is high ; and the subsequent cost of boring 

 and turning necessarily very great. 



191. In its softest state, fine cast-steel is so hard, that the difference m hard- 

 ness, between it and the hardest steel tools designed to act upon it is so slight, 

 as to involve the necessity of reducing the angle, at which the solid arris of 

 all cutting tools meets the point of section, almost to zero — hence but little 

 work done, in proportion to the labour expended, and rapid wear of the tool 

 by abrasion, which constantly requires fresh grinding to edge. When, there- 

 fore, the cost of workmanship is added to that of material — the price of 

 steel guns is, weight for weight, perhaps considerably more than that of gun- 

 metal. There is also the possibility of cast-steel in guns getting in parts 

 hardened accidentally, during the first steps of manufacture, which, if not dis- 

 covered until after boring had partly been effected, might not admit of remedy. 

 This property of steel, so valuable in most other cases, is a positive disadvan- 

 tage to it as a material for guns, affording facilities for their total destruction by 

 an enemy, or for their irreparable injury by the common accidents of confla- 

 gration and the usual means for its extinction. 



192. One important element of material for an unexceptionable gun is, that 

 its toughness should be such as to afford the fewest fragments, and no splinters, 

 in case either of the gun bursting or being knocked to pieces by the stroke of 

 shot ; this is lost totally in cast-steel, which bursts into very numerous sharp-edged 

 irregular fragments with many splinters, almost as a gun of glass might. From 

 the extremely small coefficient of extension of cast-steel, the limit in thickness 

 of a gun beyond which further increase of metal will be useless, will be sooner 

 reached with this than with any other material for ordnance. 



