370 W. G. 3/ixter — Deportment of Charcoal with 



ammonia was displaced by dry nitrogen and the tube was 

 exhausted. The product contained 2 '22 per cent of nitrogen. 

 In this and the preceding experiment considerable hydrogen 

 was set free from the ammonia. 



Experiment 3 was a repetition of % with the difference that 

 the ignition in ammonia was maintained two hours. The 

 escaping gases contained cyanogen. The lampblack contained 

 3*18 per cent of nitrogen. 



Experiment 4- — Sugar charcoal, containing 0126 per cent 

 of hydrogen and 0*04 per cent of ash, was heated to a bright 

 red heat and dry ammonia was passed over it for an hour, and 

 then the ammonia was displaced by nitrogen and the tube 

 allowed to cool. The hydrogen set free was collected over 

 water and tested by burning. The charcoal after ignition in 

 ammonia yielded 0*16 per cent of nitrogen on combustion. A 

 portion of it was heated with sodium carbonate until it disap- 

 peared, the fused mass was dissolved in water and a mixture 

 of ferrous and ferric chloride was added and the whole was 

 warmed and then cooled. On acidifying with hydrochloric 

 acid a small amount of prussian blue appeared. 



As incandescent charcoal and ammonia react to form cyano- 

 gen it may be that the last is the compound taken up by the 

 charcoal in the experiments with ammonia, since cyanogen 

 reacts with charcoal producing a nitrogenous coal as shown by 

 the following : 



Experiment 5. — Pressed lampblack was placed in one end 

 of a tube and mercuric cyanide in the other end, and the tube 

 was gently heated while dry air was passed through it to 

 remove moisture. Next the lampblack was heated to a red- 

 heat which was sufficient to decompose parac} 7 anogen, and the 

 mercuric cyanide was gradually heated so that cyanogen gas 

 passed for half an hour over the lampblack which was then 

 allowed to cool in the gas. The lampblack was next heated, 

 but not to redness, for half an hour in an exhausted tube to 

 remove occluded cyanogen. Gas ceased to come off toward 

 the end of the heating in vacuo. The product contained 

 6"48 per cent of nitrogen. It was finally heated in vacuo for 

 one hour to redness when it gave off but little gas and no 

 cyanogen. After the second heating in vacuo the lampblack 

 was found to contain 646 per cent of nitrogen. When it was 

 ignited in steam, ammonia was formed abundantly. 



Experiment 6. — Animal charcoal of unknown origin but 

 presumably from blood, as it left after burning only a small 

 amount of red ash, was heated to redness in a covered platinum 

 crucible, and then was found to contain 6 '82 per cent of 

 nitrogen. 



