372 W. G. Mixter — Deportment of Charcoal with 



solving the saline mass in water and then adding successively a 

 solution of ferrous-ferric chloride and hydrochloric acid. The 

 prussian blue reaction showed the presence of more than a 

 trace of nitrogen. 



Experiment 1<B. — IT liters of nitric oxide were passed dur- 

 ing an hour and a half through a tube containing 20 grains of 

 charcoal heated to a dull red. 8 grams of charcoal were 

 burned. The charcoal in the posterior end of the tube glowed 

 feebly and mostly disappeared and the small portion remain- 

 ing unburned contained 15 33 per cent of nitrogen, while the 

 charcoal in the anterior end contained only 96 per cent. 

 0*092 gram of ammonia was obtained by passing the gases of 

 the combustion through hydrochloric acid. 



Experiment 13. — -This was made as nearly as possible like 

 the preceding, nitrous oxide being used. The charcoal burned 

 more rapidly than in nitric oxide and with a yellow flame, dis- 

 appearing completely in the posterior end of the tube. When, 

 however, the heat was lowered to a faint red a small portion of 

 unburned charcoal next the current of gas remained which con- 

 tained 3*39 percent of nitrogen, the charcoal from the anterior 

 end yielding 0*26 per cent. The total amount of ammonia col- 

 lected in the gaseous products of the combustion was i milli- 

 grams. When the nitrogenous charcoal of this experiment 

 was heated in steam ammonia was formed. 



Experiment 11^. — 30 grams of charcoal were kept at a dull 

 red heat for three hours while 50 liters of nitric oxide were 

 passed over it. The gas was dried by sulphuric acid in three 

 wash bottles. The small portion of charcoal which remained 

 in the posterior end of the tube contained 13*79 per cent of 

 nitrogen. The nitrogen was not estimated in the remainder 

 of the coal which was found to yield cyanogen to a hot con- 

 centrated solution of potassium hydroxide. 



The charcoal used in the foregoing experiments contained 

 considerable hydrogen and oxygen, when, however, charcoal 

 nearly free from hydrogen is partly burned in nitric oxide no 

 nitrogen is retained as the following shows : 



Experiment 15. — Charcoal containing 126 per cent of 

 hydrogen and no nitrogen was nsed. 10'5 grams of dense 

 pieces were heated in a tube from which the air was displaced 

 by dry carbon dioxide. IT liters of nitric oxide dried by sul- 

 phuric acid in three bottles were passed over it in 35 minutes 

 and the highest temperature of a combustion furnace was 

 maintained. 3*7 grams of the coal were burned, the piece in 

 the posterior end of the tube falling to a powder, which was 

 found by the following test to contain no nitrogen : 0'264T 

 gram of the charcoal and 1*3 gram of potassium chlorate inti- 



