Pyrofuxin—a New Tanning Substance from Coal.
A new extract of coal is being introduced in Germany for industrial purposes, especially for tanning leather and disinfection generally, to which the name "pyrofuxin" is given by the discoverer, Professor Paulus Reinsch, of Erlangen, Bavaria. Unlike the generality of such compounds, this new material is not a derivative of coal tar, or of any of the distillates of coal, but is obtained directly from coal itself. Pit or bituminous coal contains most of it, and is prepared for treatment by being broken into nuts. The crude pyrofuxin is extracted by repeated boilings in a solution of caustic soda. The pyrofuxin enters into solution, and is allowed to stand for a time. It is then poured off, and a carbonic acid gas is passed through it. The resultant liquor has a specific gravity of 1.025 to 1.030, and holds from 10 to 15 grammes of pyrofuxin to the liter. In its purified form the compound is a fine, non-triturable substance, without taste or smell, non-poisonous, and in appearance like catechu. Some Russian coals contain 18 per cent of pyrofuxin. After the extraction of this material the coal remains combustible. It is described as being one of the most powerful and effective antiseptics known to science. On this account it is expected to be most valuable for tanning, as being twenty-eight times quicker in action than bark, and producing a better result at decreased cost.
It will be soon enough to give credence to this alleged leather tanning agent when specimens of good leather are produced.
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 |