1 



CHEMISTRY. 227 



black phosphorus depends on two things, — the state of purity to 

 which phosphorus is brought by distillation, and the temperature 

 to which it is afterwards submitted. 



Phosphorus which has been exposed to the sun is carefully dis- 

 tilled and collected in a flask, which is slowly cooled in a 

 water-bath. The product forms a transparent white mass at 

 ordinary temperatures, but if cooled down to 5° or 6° C, it sud- 

 denly turns to a beautiful black color. It can be redistilled or 

 fused; it is colorless while liquid, but becomes black on again 

 cooling to near zero. M. Blondlot regards black as the proper 

 color of phosphorus, — Comptes Bendus. 



White Fhosphorus. — M. Baudrimont shows that white phospho- 

 rus is neither a hydrate nor an allotropic state of ordinary phos- 

 phorus, nor does it result from devitrification of transparent 

 phosphorus ; but that it is ordinary phosphorus irregularly cor- 

 roded on the surface by the action of the air dissolved in the 

 w^ater, — a slow combustion, which is accelerated by the action 

 of light, and which ceases as soon as the water holds no more 

 oxygen in solution. — Comptes Bendus. 



Oreide. — Composition — copper 79.7 parts, zinc 83.05 parts, 

 nickel 6.09 parts, iron 0.28 parts, tin 0.09 parts. 



The last two ingredients are purely accidental. This alloy 

 resembles gold. 



Silver Ware may be kept bright and clean by coating the 

 (warmed) articles with a solution of collodion diluted with al- 

 cohol. 



Austrian Non-Explosive Blasting Poivder consists of 30 per cent, 

 of nitrate of potassium, 40 per cent, of nitrate of sodium, 12 per 

 cent, of sulphur, 8 per cent, of charcoal, 4 per cent, of pit-coal, 

 and 6 per cent, of tartrate of potassium and sodium. This pow- 

 der is explosive only when it has been rammed tight. 



Glijcerine in Crystals. — M. Werner, bypassing a few bubbles of 

 chlorine gas through the glycerine of commerce, obtained small 

 octahedral crystals, which are very hard, and without the sweet 

 taste of gh'cerine even when melted. — Chem. News. 



Platinum in Scotland. — Small quantities of platinum have been 

 in Scotland associated with the gold existing there in the quartz. 

 The metal is found in small scales resembling silver, but not 

 magnetic, as is much of the crude platinum found in South Amer- 

 ica. — Mining Journal. 



Topaz. — In a very difiicultly accessible cave in the mountain 

 of Galenstock, which separates the canton Of Berne from that of 

 Urich, a very rich deposit of topaz has been recently found, val- 

 ued at more than 100,000 francs. 



Salt Deposit near Berlin. — It appears that there has been dis- 

 covered near Berlin, at Sperenberg, a rock-salt deposit, which in 

 some localities has a depth of 6()9 feet, and from borings made it 

 seems in every respect to be a highly valuable mineral deposit. 



A new Crystalline Form of Silica. — De Rath has found, in a vol- 

 canic porphyr}' from Cerro San Cristobal, Mexico, a mineral he 

 calls tridymite, wliich is pure silica, of the density of what has 

 heretofore been regarded as •' amorphous " silica, 2.3; the den- 



