S92 



Prof. Johnston on the Composition of certain 



The fossil wax examined by Magnus, seems to have been 

 identical with that of Malaguti, only it melted at 82° C. 



The inspection of this table shows that these mineral pro- 

 ducts contain at least four substances, possessed of different 

 properties, chemical and physical, of which three are present 

 in that from Urpeth Colliery. 



1. One charred by sulphuric acid and insoluble in aether. 

 — (//. Malaguti.) 



2. One soluble in cold aether. — (/. and IL B.) 



3. One soluble in boiling aether, and sparingly in boiling 

 alcohol.— (//. B. III. C.) 



4?. A residual portion of greater density scarcely acted on 

 by either of these menstrua. — (///. D.) 



The different substances composing the ozocerite appear as 

 I have already stated to be identical in chemical constitution, 

 being entirely composed of carbon and hydrogen, in the same 

 proportions as in olefiant gas. That the substance from Ur- 

 peth Colliery contains no oxygen, is proved by its not affect- 

 ing the lustre of potassium, when melted along with it. The 

 carbon and hydrogen were ascertained by burning with oxide 

 of copper. 



1. 8*43 grs. of the crude mass, freed by fusion from ad- 

 hering earthy matter, gave 10-69 grs. of water, or 1*187 

 grs. of hydrogen. 



2. 5*4:7 grs. of the matter taken up by aether, gave 6*92 

 grs. of water, or 0*77 grs. of hydrogen. 



.*}. 5*84- grs. of the same gave 7*39 grs. of water and 18*32 



grs. of carbonic acid. 

 4. 5*47 grs. of the same gave 6*72 grs. of water and 16*58 



grs. ofcarbonic acid. 



