Weight and Power of Modern Guns.—Table of Armstrong Guns. | ||||||
|---|---|---|---|---|---|---|
| Gun. | Caliber. | Weight. | Total Length of Gun. | Length of Bore. | ||
| in. | in. | tons. | calibers. | in. | calibers. | in. |
| 4.724 | 4.724 | 2.5 | 24 | 112.7 | 22 | 104.0 |
| 4.724 | 4.724 | 2.2 | 35 | 165.3 | 33 | 156.6 |
| 6.0 | 6.0 | 4.0 | 28 | 166.4 | 26 | 156.2 |
| 6.0 | 6.0 | 4.5 | 32 | 192.0 | 30 | 180.0 |
| 6.0 | 6.0 | 5.5 | 37 | 222.0 | 35 | 210.0 |
| 7.0 | 7.0 | 7.0 | 2 8 | 196.0 | 26 | 182.0 |
| 7.0 | 7.0 | 8.0 | 32 | 224. 0 | 30 | 210.0 |
| 7.0 | 7.0 | 9.0 | 37 | 259. 0 | 35 | 245.0 |
| 8.0 | 8.0 | 11.5 | 28 | 222. 5 | 26 | 208.0 |
| 8.0 | 8.0 | 12.5 | 32 | 256. 0 | 30 | 240.0 |
| 8.0 | 8.0 | 14. 0 | 37 | 296. 0 | 35 | 280.0 |
| 9. 2 | 9. 2 | 19. 0 | 28 | 257. 6 | 26 | 238.7 |
| 9.2 | 9.2 | 21.5 | 32 | 287.3 | 30 | 267.8 |
| 9.2 | 9.2 | 24.0 | 37 | 340.4 | 35 | 322.0 |
| 10.0 | 10.0 | 25.0 | 28 | 274.0 | 26 | 254.5 |
| 10.0 | 10.0 | 27.0 | 32 | 320.0 | 30 | 300.0 |
| 10.0 | 10.0 | 30.0 | 37 | 370.0 | 35 | 350.0 |
| 12.0 | 12.0 | 43.0 | 28 | 331.0 | 26 | 307.5 |
| 12.0 | 12.0 | 46.0 | 32 | 384.0 | 30 | 360.0 |
| 12.0 | 12.0 | 51.0 | 37 | 444.0 | 35 | 420.0 |
| 16.25 | 16.25 | 93.0 | 28 | 455.0 | 26 | 422.5 |
| 16.25 | 16.25 | 110.0 | 32 | 520.0 | 30 | 487.5 |
| 16.25 | 16.25 | 127.0 | 37 | 601.3 | 35 | 568.75 |
| 17.0 | 17.0 | 100.0 | 28 | 468.0 | 26 | 442.0 |
| 17.0 | 17.0 | 116.0 | 32 | 544.0 | 30 | 510.0 |
| 17.0 | 17.0 | 137.0 | 37 | 629.0 | 35 | 595.0 |
| Weight and Power of Modern Guns.—Table of Armstrong Guns. (continued) | ||||||
| Weight. | Muzzle Velocity. | Total Energy | Energy per Ton Weight of Gun. | Energy per Inch of Shot's Circumference. | Thickness of Wrought Iron Plate the Shot is Capable of Perforating. | |
| Charge. | Projectile. | |||||
| lb. | lb. | ft. per sec. | ft. tons. | ft. tons. | ft. tons. | in. |
| 12 | 40 | 1,680 | 783 | 522.0 | 53.1 | 7.0 |
| 16 | 40 | 2,078 | 1,198 | 532.4 | 81.3 | 9.1 |
| 42 | 80 | 2,060 | 2,354 | 588.5 | 125.7 | 11.6 |
| 45 | 100 | 1,940 | 2,610 | 580.0 | 139.4 | 12.2 |
| 60 | 100 | 2,146 | 3,193 | 580.5 | 170.5 | 13.5 |
| 60 | 120 | 2,050 | 3,497 | 466.3 | 160.2 | 13.0 |
| 75 | 145 | 2,020 | 4,075 | 479.4 | 186.6 | 14.1 |
| 80 | 145 | 2,140 | 4,604 | 511.5 | 210.9 | 14.9 |
| 120 | 180 | 2,177 | 5,915 | 514.3 | 236.9 | 15.8 |
| 120 | 200 | 2,157 | 6,452 | 537.6 | 258.4 | 16.5 |
| 130 | 210 | 2,236 | 7,280 | 520.0 | 291.5 | 17.5 |
| 175 | 320 | 2,060 | 9,412 | 495.3 | 327.5 | 18.5 |
| 200 | 380 | 2,035 | 10,923 | 508.0 | 380.1 | 20.0 |
| 230 | 380 | 2,375 | 14,800 | 616.6 | 515.0 | 23.2 |
| 200 | 450 | 1,910 | 11,383 | 455.3 | 364.2 | 19.5 |
| 270 | 470 | 2,185 | 15,560 | 576.3 | 497.9 | 22.8 |
| 270 | 500 | 2,213 | 16,979 | 566.0 | 543.3 | 23.8 |
| 330 | 700 | 2,087 | 21,141 | 491.6 | 563.1 | 24.2 |
| 400 | 800 | 2,117 | 24,861 | 540.4 | 662.2 | 26.2 |
| 450 | 850 | 2,205 | 28,665 | 562.0 | 763.6 | 28.1 |
| 850 | 1,800 | 2,106 | 55,377 | 595.4 | 1,088.7 | 33.5 |
| 900 | 1,800 | 2,216 | 61,200 | 556.4 | 1,203.2 | 35.2 |
| 900 | 1,800 | 2,295 | 65,745 | 517.6 | 1,292.6 | 36.5 |
| 827 | 2,000 | 1,932 | 51,790 | 517.9 | 973.1 | 31.7 |
| 1,000 | 2,000 | 2,190 | 66,512 | 573.3 | 1,249.7 | 35.8 |
| 1,000 | 2,000 | 2,255 | 70,520 | 514.7 | 1,325.0 | 37.0 |
Castner's New Method for Producing Sodium.
This new method, heretofore mentioned by us, is now being successfully worked in London, and is thus described in Engineering:
Up to the present this novel method of manufacture has been kept rather secret, but now, owing to the success achieved by a plant erected and worked on a commercial scale, we are enabled, through the courtesy of Mr. H. Y. Castner, to lay before our readers an outline sketch of the method of operation which is followed, and which we have seen carried out with success at his works, 65 Belvidere Road, Lambeth. Few persons outside of the chemical profession are aware of the commercial existence of the metal sodium or of its uses, and even among those following that profession but little is known, except that it is used in the manufacture of aluminum, and is very expensive. Much has lately been published in various scientific journals throughout the world upon the subject of alleged new processes, whereby that highly interesting metal—aluminum—might be cheaply produced without sodium, and thus be made to take in the commercial world a place to which its varied valuable properties entitle it. So far nothing has resulted from these numerous so-called discoveries, and at the present time the only process in use whereby aluminum can be produced is that devised by and due to Deville's ingenuity.[1] This process has been called the sodium process, apparently to distinguish it from others, but seeing that it is the only process which has ever proved practical, it is somewhat of a mystery why it needed to be so distinguished.
The late Dr. Walter Weldon, in a paper read before the Society of Chemical Industry a few years ago, clearly resolved the great question of cheaply producing aluminum, and showed by argument that this end was only to be gained in either of the two following directions, namely, first, by the production of cheap sodium and the employment of Deville's process, and second, by the discovery of a substitute for sodium, which has hitherto given to aluminum its excessive cost in production. After twenty-five years of research by some of the best scientists of the present age, no substance has been found that will replace sodium, and although every known substance has, at various times, been proposed, none has been successful. So discouraging has been the research, that those familiar with the subject have almost abandoned hope of ever seeing aluminum cheaply manufactured by chemical processes, believing also that Weldon's first proposition was an impossibility.
It is not the purpose of this article to enter into a lengthy discussion of Mr. Castner' process of producing sodium, as Mr. James Mactear, F.C.S., is about to prepare a scientific paper on the subject, to be read on March 7 before the Society of Chemical Industry. We shall content ourselves by presenting to our readers a short practical description of the process and its results.
Before doing so it will, however, be advantageous to give a short account of the method by which sodium has hitherto been separated from its compounds, in order that a clearer conception of the features in which the new process differs from the old one may be obtained. At high temperatures carbon has the property of separating sodium from its oxygen compounds, carbon uniting with the oxygen to form carbonic oxide, the sodium being thereby liberated. In the usual process this reaction is brought about by mixing carbonate of soda, lime, and carbon in small wrought iron cylinders, and exposing them to an intense heat, when a part of the sodium comes off as vapor. The lime is added to prevent fusion, for were the mass to melt, the carbon would float on the top, and could no longer attack the soda. The new process differs from the old principally in working with a fused mass of soda compound, this operation having been rendered feasible by the most ingenious device of weighting every particle of carbon with iron, so that the two chemicals—soda and carbon—are kept in perfect admixture, and are continually presenting fresh surfaces to each other as the liquid circulates in the crucible under the action of the heat. By this simple but beautiful plan of weighting the carbon, it is rendered possible to employ a soda compound which is decomposed at a much lower temperature than that hitherto used, and to carry on the process in large and durable vessels, instead of in small cylinders, which have a very short life. Having thus given a short account of the chemical process, we will describe the commercial method of manufacture.
The operations are carried on in large cast steel crucibles, and the charges consist of caustic soda and a finely ground artificial compound of carbon and iron, which is the reducing agent. This compound is made by coking a mixture of fine iron and pitch. The crucibles containing these materials are first heated in a small furnace at a low temperature, the object being to expel the hydrogen from the caustic alkali and bring about quiet fusion. The crucibles are then removed from this furnace, by means of a little truck, and placed upon a movable platform, which is operated by hydraulic power. They are then by this means raised into the large furnace, where the crucible covers are fixed stationary. The edges of the crucible and cover coming together form a tight joint, and from this cover projects a small tube to the outside of the furnace into a narrow rectangular box, known as the condenser. The reduction of the sodium commences soon after the crucible containing the charge is in its place, the vapors and gases passing from the fused mixture through the exit pipe from the cover into the condenser, where the metallic vapors are condensed to metal, while the uncondensed gases escape by a small outlet tube. After the charge is exhausted, the crucible is lowered, and one containing a fresh charge raised in its place; in this manner the process might almost be called continuous.
The actual temperature used in this process to bring about reduction, as measured by experts, has been found to be 850° Cent. By the older method the temperature necessary is about 1,400° Cent. This is practically the great point of economy in this process, as the high price of sodium has hitherto been owing to the excessive heat used in the older process and the consequent destruction of the wrought iron vessels. Sodium at present costs about four shillings per pound to produce, while the materials necessary for this quantity, were nothing wasted, would hardly cost four pence. The difference between these two figures represents the wear and tear to the furnace, the destruction of the wrought iron cylinders, the loss and waste of materials, the excessive labor and care necessary to employ in manufacturing, and fuel. Approximately, the cost of these items in producing one pound of sodium by the older process is as follows: