2 ART. S. — DIVERS AND OGAWA : PREPARATION OF 



thus become certain that sulphamide is a little soluble in absolute 

 alcohol and even very slightly so in dry ether, that it melts at 

 91°, and that its silver derivative is insoluble in ammonia alone, 

 but soluble in ammonia in presence of the ammonium nitrate 

 which its mother-liquor always contains. The publication of 

 Hantzscii and Hole's important contribution to the knowledge 

 of sulphimide and sulphamide (Ber., 1901, 34, 30), in which 

 Traup.e's account of sulphamide (Ber., 1893, 26, 609) is amended, 

 affords welcome confirmation, so far as it goes, of the correctness 

 of our own observations. 



Hitherto, as well is known, sulphamide has only been got from 

 sulphuryl chloride and ammonia, a mode of preparing it which 

 Hantzsch and Hole have shown to be most laborious and un- 

 profitable, and the difficulty of getting it in this way has quite 

 recently induced Ephraim to try to obtain it from sulphuryl 

 chloride by means of urethane, but without success (Ber., 1902, 

 35, 77G). Sulphuryl chloride is stated to give only 1-2 per cent. 

 of pure sulphamide, whilst ammonium amidosulphite, by a process 

 not unduly troublesome, yields 10 per cent, of its weight, and 

 probably much more by skill and care. In order to prepare the 

 ammonium amidosulphite and decompose it afterwards, ammonia 

 in excess and sulphur dioxide are led into a closed flask, fitted 

 with a thermometer and an exit-tube dipping in mercury. To 

 absorb the heat caused by the combination of the gases, the 

 flask is held in a bath of brine and crushed ice, which is more- 

 effective when the flask contains some ether and is kept in motion, 

 because then the salt does not stick to the walls of the flask as 

 a. waxy, badly-conducting coating. The rate of flow of the gases 

 is to be regulated by the operator's ability to prevent the tem- 

 perature in the flask from rising much above 10°. The inside 



