326 Dr Bischof'b Examination of Three Inflammable Gases 



After the cooling of the apparatus, I perceived the same em- 

 pyreumatic smell as iu the former experiments, but in greater 

 intensity. It was not unlike that of oil of turpentine or of 

 petroleum. The partially decomposed gas had likewise an 

 empyreumatic smell, quite similar to the products of the dry 

 distillation of wood, or still more of sugar. The gas burned 

 with a feeble bluish flame, which was coloured yellow only at 

 the tip. The carbon which was deposited in the tube pos- 

 sessed the same metallic lustre, and presented the same ap- 

 pearance of rolled up lamellae, as in the former experiments. 

 Some of these lamellae had a diameter of 2 lines. I likewise 

 found a dull soot-like powder. The internal surface of the 

 tube itself had a black coating, which adhered very strongly. 

 I attempted to loosen it by means of a feather moistened with 

 alcohol, but I only succeeded with a very small quantity. By 

 filtering the liquid, little portions of carbonaceous dust remain- 

 ed behind, and the filtered alcohol was coloured slightly yel- 

 low. Ether seemed to have no eftect. Sulphuric acid was 

 rendered somewhat brownish when a glass rod moistened with 

 it was rubbed upon the coating. 



It must likewise be remarked, that at the end where the 

 dry pit-gas entered, the coating was brownish-yellow, but in 

 the other parts of the porcelain tube, quite black. Hence it 

 appears that the feebler heating of that portion of the tube 

 gave rise to other products than the stronger heat of the other 

 parts. The little tubes of carbon exhibited a certain consist- 

 ence. They could be strongly shaken in a glass without be- 

 ing broken, and I had even difficulty in dividing them with a 

 glass rod. On being rubbed, they coloured paper like gra- 

 phite, and the mark was removed by Indian rubber. 



The deposited charcoal was not acted on by nitric acid in 

 the cold. When exposed to a boiling temperature, there ap- 

 peared to be a feeble action. At least, after the boiling had 

 ceased, the evolution of some gas bubbles could be remarked, 

 which probably consisted of carbonic acid. The metallic glance 

 of the carbon was, however, not destroyed in the acid. 



It follows from these experiments, that the carburetted hy- 

 drogen is decomposed by heat not merely into hydrogen and 

 carbon, as has been hitherto generally believed, but that, be- 



