460 Scientific Intelligence. 



SCIENTIFIC INTELLIGENCE. 



I. Chemistry and Physics. 



1. A Neio Formation of Diamond. — In a lecture delivered 

 before the British Association at Kimberly, South Africa, Sept. 

 5, 1905, Sir William Crookes stated that he had found what 

 were, in all probability, microscopic diamonds in residues obtained 

 by Sir Andrew Noble in exploding cordite in closed steel cylin- 

 ders. Crookes had calculated the theoretical melting point of 

 carbon as 4400° absolute, and the melting pressure as 16'6 atmos- 

 pheres ; hence he concluded that the conditions of the cordite 

 explosions, where a. pressure of 8000 atmospheres and a tempera- 

 ture reaching in all probability 5400° absolute, would be favor- 

 able for the formation of diamonds. Upon examining the resi- 

 dues from such explosions, octahedral crystals were found which 

 had high index of refraction, the proper cleavage, and the 

 absence of birefringence of the diamond, and, although their 

 other properties have not yet been determined, the chemical 

 ordeal to which they were subjected in the treatment of the 

 material leads to the belief that they must be diamonds. — Chem. 

 News, xcii, 148. h. l. w. 



2. A New Compound of Ir 07i. — Otto Hatjser has prepared 

 a curious ammonium-ferrous-ferric basic carbonate, evidently a 

 triple salt, to which he gives the formula 



Fe // 2 NH 4 Fe'"0(C0 3 ) 3 .2H 2 0. 



It may be prepared, in the form of a crystalline precipitate, as 

 follows : Ammonium-ferrous sulphate is dissolved in five parts of 

 water, then a solution of commercial ammonium carbonate in 

 about five parts of water is added until the precipitate which 

 forms at first has redissolved. The quickly filtered liquid is then 

 placed in a loosely closed bottle where only a small surface of 

 the solution is exposed to the air. The liquid now becomes 

 brown very rapidly from the top downward without any separa- 

 tion of ferric hydroxide, and in about half an hour a slightly 

 greenish precipitate settles to the bottom, and after about two 

 days the iron is completely removed from the solution in the 

 form of the new compound. The substance has a light green 

 color when fresh, but it rapidly darkens upon exposure to the 

 air. It dissolves readily in acids with effervescence ; it gives a 

 black ferrous-ferric oxide with alkalies, and at the same time 

 evolves ammonia. — Berichte, xxxviii, 2101. h. l. w. 



3. Nitrosyl Fluoride. — Ruff and Stauber, by the action of 

 nitrosyl chloride upon silver fluoride have prepared this substance, 

 NOF. It is a colorless gas which melts at about —134° and 

 boils at —56°. In its chemical activity it resembles free fluorine 



