& 



Notices of the Labours of Continental Chemists. 41 



It is somewhat remarkable that this is identical with the 

 composition which Dr. Ettling found for creasote. 

 Analysis of creasote by Ettling. 



Carbon 75*56 



Hydrogen 7*78 



Oxygen ~ 16'66 



100-00 



As, however, I have not been able to determine the atomic 

 weight of salicone, I do not think it worth while deducing 

 any formula from these numbers. When salicine is destruc 

 tively distilled without any lime, it also yields an empyreuma 

 tic oil. 



Glasgow, April 10, 1841. 



VII. Notices of the Results of the Labours of Continental 

 Chemists. By Messrs. W. Francis and H. Croft. 



[Continued from vol. xviii., p. 546. J 



Action of High Temperature on Mellitate of Ammonia. By 

 F. Wohler. 



I T might with some probability be supposed that the honey- 

 •*■ stone or mellite is contained in the mass of the brown coal 

 of Artern in such small particles as to escape observation. 

 According to Wohler's experiments, however, this is not the 

 case. The substance which remains after the mineral has been 

 treated with carbonate of ammonia is alumina; but it always 

 contains a little mellitic acid, probably as basic salt, for on 

 dissolving in nitric acid and evaporation, small crystals are 



obtained, which are regenerated mellite, Al Me 3 +18 aq. Mel- 

 litate of ammonia loses ammonia by boiling, and is converted 

 into an acid salt; if, therefore, the mineral has been boiled 

 with the carbonate, it may easily happen that an acid salt is 

 formed, and thereby alumina dissolved. This alumina then 

 passes into the lead or silver salts, from which the acid is 

 then obtained in an impure state, viz. containing alumina. 

 It is therefore better, on decomposing the mellite with carbon- 

 ate of ammonia, to add a few drops of caustic ammonia from 

 time to time. The acid ammonia salt is much more soluble 

 than the neutral one. The acid crystallizes from a concen- 

 trated solution in fine silky needles; does not lose water 

 when heated to 200° C. Formula, C 4 O 3 + H 2 O. Wohler for- 

 merly stated that nitric acid precipitated a somewhat insoluble 

 salt from the neutral mellitate of potassa ; this is, however, not 



