IMPROVEMENTS IN THE MECHANICAL MEANS EMPLOYED.
The great difficulty, since the invention of Heath in 1839, has been in the application of mechanical means to effect the decarbonization of cast metal to form wrought iron, and the recarbonization to form steel. The means employed by Mr. Bessemer are the best which have been applied, but perhaps not the best that may be applied. There is always room for invention; and American inventors proverbially lead all others in mechanics. Give them the inducement and an idea, tell them what you want and what you will pay, and if the reward is worthy of the object you will be sure to realize your wishes.
There is no wider field for invention, no greater reward offered to industry or inge nuity, than may be found in the full development of our resources of coal 4nd iron, and the realization of their wealth by science and art, provided, however, that our domestic industry is protected and encouraged.
This globular converter is a decided improvement on the egg-shaped converter, both in the economy and effect of the application. The blast-pipe is simple, and can be lowered into and elevated out of the converter at pleasure, and can be repaired without hin drance to the operations, which cannot be done in the egg converter, since the con verter must be cooled and remain idle while the tuyers, &c. are being repaired. The converter being spherical has more surface, and the metal will expose a greater surface and a less depth to the blast, and, consequently, requiring a smaller amount of pressure to penetrate the liquid mass.
But improvement will not stop at this. While the works erected by Mr. Bessemer in England exhibit great mechanical skill, substantiality, and enormous cost, they do not manifest the ingenuity which generally characterizes American inventions. There is an evident want of simplicity and economy in the Bessemer arrangements, which do.not admit of application to old establishments without great cost and alteration.
The great first principle involved—that of blowing air into molten cast metal—cannot be secured to any inventor, since it has been in use for ages; but the mechanical means of applying the blast, and the general arrangement of the apparatus, are as open to in vention and improvement to-day as they were one hundred years ago.
Having briefly traced the modes and means by which iron and steel have been elabo rated from the ore since the early development of the art of smelting to the present time, we may now sum up the facts, and thus be enabled to comprehend more clearly the present status of these great and important branches of our manufacturing industry.
1. Rich and pure iron ores will always produce good iron in the blast-furnace if pure fuel is used ; and charcoal iron is always superior to that produced by mineral fuel, because charcoal contains less impurity than the best mineral coal.
2. All ores must go through a process of torrefaction and oxidization before they can be successfully smelted or reduced to iron ; and the smaller the particles of ore, and the more intimately these can be brought in contact with carbon under a strong heat, the sooner and more thoroughly will this process be completed.
3. The principle applied in the blast-Turnace for the reduction of ores to cast iron is the simplest and most economical that has yet been made use of or suggested, and it seems impossible that any better mode can be applied. The only desirable improvements we can now appreciate are the preparation of the ores for easy and full deoxidization, the increase of temperature in the blast by utilizing the furnace-gases, and the use of the caloric given off by burning coal without its impurities.
4. The decarbonization of cast iron while in a fluid condition direct from the blast furnace by the use of air blown through the liquid mass, in place of the tedious, costly, and imperfect process of puddling, and the recarbonization and purification of the iron by the proper admixture of carbon and manganese.
The modes of effecting these improvements are plainly set forth by the requirements, while the means are simply those now in daily use. We only need combination and skilful mechanism to develop our iron-industry in a state of perfection to our present comprehension ; the production of superior wrought iron and steel from good ordinary ores with mineral fuel at a cost but little exceeding cast iron.
The limits of this work will not admit a full illustration of these improvements. We have far exceeded the space originally allotted us on the subject of iron, and can only add, in conclusion, an earnest hope that our brief notice may not only aid in directing our readers to the accomplishment of the desired economy in the development of our mineral resources, but encourage such legislation as will lead to the realization of their immense wealth at an early day.
The statistics of iron will be found in the Appendix.