NEF. — BIVALENT CARBON. 175 



mylchloridoxime with ammouia, isuretine and ammonium chloride 

 would be formed. The reaction takes place, however, in a different 

 manner, no matter whether the ethereal solution of formylchloridoxime 

 is treated with concentrated aqueous, or with dry gaseous ammonia. 

 It is best to proceed as follows. The ethereal solution, obtained by 

 extracting the acidified sodium fulminate solution, is treated directly, 

 without concentrating it, in a separatory funnel with small quantities 

 of concentrated aqueous ammonia (30 per cent), taking care to shake 

 well and to cool thoroughly with water. A yellow powder separates 

 out in large quantity, which settles on shaking in the lower portion 

 of the funnel. A portion from 32 grams of mercuric fulminate was 

 always worked up at a time, and about 40-50 c.cm. concentrated 

 ammonia used (until a strong smell of ammonia is apparent). The 

 aqueous solution with the yellow powder suspended in it, is then 

 drawn off and filtered, and the filtrate again brought into the sepa- 

 ratory funnel, and the operation repeated until all the yellow powder 

 is brought on the filter ; it is then dried on clay plates. The filtrate 

 contains much ammonium chloride and also some of the yellow sub- 

 stance, which is sparingly soluble in cold water. 25 grams of the 

 yellow powder were regularly obtained from 96 grams of mercury 

 fulminate: it consists of the secondary ammonium salt of cyaniso- 

 nitrosoacethydroxamic acid ; it cannot be crystallized from hot water 

 however without some decomposition. The yellow powder is there- 

 fore converted directly into the free acid. 25 grams of the salt are 

 suspended in 40 c.cm. water, and 120 c.cm. dilute hydrochloric acid 

 (16.5 per cent) added, and thereupon the resulting solution is extracted 

 35 times with ether. After drying with chloride of calcium, the ethereal 

 solution is distilled off and 15 grams of a colorless solid remains, 

 which already consists of practically pure cyanisonitrosoacethydrox- 

 amic acid. The substance is recrystallized from ether with addition 

 of a small amount of ligroine (bpt. 70°-80°), and obtained in colorless 

 cubes or in 4-sided prisms, clear as glass, and melting, with decompo- 

 sition, at 117°-118°. 



0.1555 gram substance, dried over HoSO^ in a vacuum, gave 0.1490 



gram COg and 0.0438 gram HgO. 

 0.1125 gram substance, gave 30.5 c.cm. Nj at 20° and 751 mm. 



