APPENDIX. 



671 



no trace of cyanogen or of any of its compounds can be discover- 

 ed. In such experiments it is necessary to employ so much al- 

 kaline hydrate, that the whole carbon of the matter be oxydizefl 

 by the oxygen of the water of the hydrate. The mixture in the 

 decomposing tube, after the process is finished, must be quite 

 white. In proportion to the richness of the organic body in car- 

 bon, and according to the temperature, there are given out along 

 with the ammoniacal gas other permanent gases, as the gas of 

 marshes, hydrogen gas, olefiant gas, or a mixture of these, and 

 in many cases liquid compounds of carbon and hydrogen, or at 

 least drops of oily matter. 



To the bodies richest in azote belong melamin, mellon, cyano- 

 gen, and its compounds. But they all contain as much of (or 

 more) carbon in proportion to their azote, as is sufficient by its 

 oxydizement to set free a sufficient quantity of hydrogen to con- 

 vert the whole azote into ammonia. In some of these compounds, 

 as mellon, whose formula is C 6 Az 4 , and melamin, which is C 6 

 H 6 Az 6 , the decomposition, when a sufficient quantity of alka- 

 line hydrate is employed, goes on and is completed without the 

 evolution of any permanent gas. All the carbon is converted 

 into carbonic acid, which remains combined with the alkali, while 

 all the azote is converted into ammonia, which flies off in the 

 state of gas, but is absorbed by the muriatic acid placed in the 

 tube to collect it 



The process employed by Varrentrapp and Will for collecting 

 the ammonia from the decomposition of bodies containing azote 

 is founded upon the facts that have been just stated. The orga- 

 nic body is mixed with a sufficient quantity of hydrate of potash 

 or hydrate of soda, previously mixed with caustic lime. It is put 

 into a crown glass tube from 16 to 18 inches long, and about 3 



