Pyrofuxin—a New Tanning Substance from Coal.
Reading edition
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