a new Mineral of Organic Origin. 467 



Sulphuric acid readily carbonizes Tasmanite, torrents of sulphu- 

 rous anhydride being disengaged at the same time. 



Aqueous solutions of the alkalies appear to be without action 

 on Tasmanite. 



Alcohol, ether, bisulphide of carbon, benzole, turpentine, 

 mineral turpentine, and paraffine oil do not appear to exert the 

 least solvent action upon Tasmanite, even on the application of 

 heat : the result might be different under an increased pres- 

 sure. 



When Tasmanite is heated in the air, it burns readily with a 

 very smoky flame and offensive odour. Submitted to destructive 

 distillation, it fuses partially and yields oily and solid products 

 having a disagreeable smell, recalling that of some specimens of 

 Canadian petroleum. One is tempted to suggest that the natural 

 rock-oils may in some instances originate in the action of heat 

 upon substances similar to Tasmanite shale. 



Composition of Tasmanite. — Qualitative analysis of Tasmanite 

 showed it to contain not only a large quantity of carbon and hy- 

 drogen, but also a very considerable proportion of sulphur; and 

 it was found that the most careful mechanical treatment of the 

 specimens failed to separate from them completely the mineral 

 impurities. That the sulphur detected was an integral part of 

 the carbonaceous matter itself, and was not owing to the presence 

 of an inorganic sulphide or sulphate, was proved in several ways, 

 and was further confirmed by the observation that the more 

 completely the mineral matter had been removed, the more sul- 

 phur was found in the specimen of Tasmanite operated upon. 



I am indebted to my friend Mr. W. H. Perkin for the first 

 four of the following analyses of purified Tasmanite. In Nos. I., 

 II., and III. the substance was burnt in a current of air, and 

 finally of oxygen, the sulphurous acid being absorbed by binoxide 

 of lead; in analysis IV. the combustion was performed with 

 chromate of lead. In analysis V. to XI. the sulphur or the ash 

 were alone determined. The sulphur was obtained by oxidizing 

 the mineral with strong nitric acid and bichromate of potassium 

 in a capacious flask, diluting largely with water when complete 

 solution had been effected, filtering to separate the silica of the 

 ash, and precipitating with nitrate of barium. After standing- 

 twelve hours, the precipitated sulphate of barium was collected, 

 washed completely; and ignited with the usual precautions. In 

 analysis V. the sulphur was oxidized by means of the gradual 

 addition of chlorate of .potassium instead of bichromate to the 

 mixture of nitric acid and Tasmanite. The mineral must be 

 completely destroyed and dissolved in order to extract the whole 

 of the sulphur. The two preparations submitted to analysis are 

 distinguished as a and b. 



