Chemistry and Physics. 71 



oxygen, over platinum sponge. For this purpose a piece of com- 

 bustion-tube about 90 cm long and 2 cm in diameter, is divided into 

 two nearly equal chambers by a constriction, a small lateral tube 

 rising from the constricted portion. Immediately beyond this 

 the tube is packed with fragments of platinum sponge ; and on 

 the other side of it is placed a large platinum boat containing the 

 phosphoric oxide previously compressed into cylinders. The 

 platinum sponge is heated to redness and a current of oxygen is 

 supplied at the end of the tube and also at the middle by the 

 lateral tube above mentioned. The sublimed product is received 

 in a tube sliding into the combustion-tube near its end, from 

 which it is pushed into a well dried bottle. As thus prepared, 

 the phosphoric oxide no longer reduces a solution of silver-nitrate 

 nor one of mercuric chloride. Nor does its solution on evapora- 

 tion and ignition give the odor of phosphine. It doubtless 

 contains a little metaphosphoric acid. The authors find that the 

 last traces of the lower oxides are not removed by this roasting 

 in oxygen even for weeks, — J. Chem. Soc, lxiii, 475, April, 1893. 



G. F. B. 



7. On the Constitution of Hydroxylamine. — In view of the 

 fact that hydroxyl compounds of nitrogen give up more or less 

 readily the elements of water to form new nitrogen compounds, 

 Kolotoff has sought by acting on hydroxylamine with ammonia 

 to bring about the reaction NH 2 . OH-hNH 3 = N 2 H 4 + H 2 0. It 

 was found, however, that this reaction did not take place even 

 when the two substances were heated together at 100° for 24 

 hours. He therefore concludes that free hydroxylamine contains 

 no hydroxyl and that its formula should be H 3 N : O. Moreover, 

 it is known that when a salt of hydroxylamine is treated with a 

 solution of bromine in an excess of strong sodium hydroxide only 

 half its nitrogen is evolved in the free state, the other half being 

 probably oxidized to acid, according to the equation: 



(NH 3 0) 2 = NH 3 +HNO+H 2 



the ammonia itself being subsequently oxidized. To test this 

 view the author oxidized in the cold a weighed quantity of a 

 hydroxylamine salt, dissolved in a large excess of NaOH, with 

 the theoretical quantity of bromine required by the above equa- 

 tion. After removal of the excess of soda the solution was pre- 

 cipitated with copper sulphate, the precipitate collected, dried 

 and weighed. Its mass was 4*9 grms that required by theory being 

 4-agrms. corresponding to the formula Cu(NO) 2 .H 2 0. It does 

 not lose weight when heated to 136° but blackens when treated 

 with soda. The author considers it to be the dihydrogen cupric 

 salt of an acid H 4 N 2 3 which he calls "pyrohyponitrous acid." 

 Hydroxylamine sulphate loses weight at 125°-130°, very rapidly 

 at 136°, the maximum loss being 28-4 per cent. The ratio be- 

 tween the nitrogen and sulphur in the residue seems to suggest 

 formation of salts of both N 2 H 4 and N 2 H 2 . — J. Soc. Chim. Russe, 

 xxiii, 3; J. Ckem. Soc. London, lxiv, (ii), 114, March, 1893. 



G. F. B. 



