For all purposes crucible-steel has proved to be superior to all others; it is well known to all experienced and observing workers in steel that, given an equal composition, crucible is stronger and more reliable in every way than any of the other kinds of steel.
This may read like a mere dictum, and it might be asked properly, What are the proofs?
The proofs are wanting for two reasons: first, because crucible-steel is so expensive that except for gun parts, armor, and such uses where expense could be ignored, crucible-steel never came into extensive use for structural purposes; second, that while thousands upon thousands of tests of the cheaper steels are recorded and available to engineers very few of such tests have been made on crucible-steel, simply because it has not been used for structural purposes.
On the other hand, intelligent makers of crucible-steel have for self-preservation made careful study of the relative properties of the different steels in order that they might know what to expect from the cheaper processes. In this way they have surrendered boiler-steel, spring-steel, machinery-steel, battering-tool steel, cheap die-steel, and many smaller applications; not because they could not produce a better article, but because the cheaper steels met the requirements of consumers satisfactorily, and therefore they could not be expected to pay a higher price for an article whose superiority was not a necessity in their requirements.
Still this stated superiority is proven best by the fact that many careful consumers who have special reasons for studying durability as against first cost adhere to the higher priced crucible-steel for such uses as, for instance, parts of mining- and quarrying-drills, high-speed spindles, in cotton-mills, and in expensive lathes and machines of that kind.
This sort of testimony should be more conclusive than that of interested steel-makers, because these men pay their own money for the higher priced material, and because men who are most careful of the quality of their produce and of their reputation are the most clear-headed and most sensible men of their class; they have the best business and the greatest success. Such men are not fools; they may be depended upon to try everything of promise with the greatest care, and to use only that thing which pays them best. In fact such men do use the cheaper steels freely wherever they can do so safely.
A good car-spring, carriage-spring, or wagon-spring is made from Bessemer or open-hearth steel, a spring that will wear out the car or carriage; it would be stupid then to buy more expensive steel for such purposes, for even if crucible-steel would wear out two cars or two wagons the owner never expects to take the springs out of an old wagon to put them under a new one.
On the other hand, the watch-spring maker or the clock-spring maker will find a great advantage in using the very best crucible-steel that can be made.
A sledge, a maul, or a hammer can be made of such excellent quality from properly selected Bessemer or open-hearth steel that it would be foolish for makers of such tools to continue to buy crucible-steel, even though they knew it to be superior, for lower first cost in such cases outweighs superiority that cannot be shown for a number of years.
Locomotive-boilers, crank-pins, slide-rods, connecting-rods, and springs can be made of such good quality of Bessemer or open-hearth steel that, like the “one-horse shay,” the whole machine will wear out at the same time practically, and that a good long time; there would be no reason in this case for using crucible-steel for one or more of these parts, although twenty-five years ago it was by means of crucible-steel that engineers learned to use steel for these purposes.