354 A NEW VARIETY OF ASPHALT. 



Thrown into boiling water it became softer to the nail, but could not be moulded between 

 the fingers. Held in the flame of a candle in such manner as to prevent as much as pos- 

 sible the action of oxygen, it gave evidence of incipient fusion, and adhered to pamper when 

 placed in contact with it. Thrown into boiling coal tar pitch, it softened, could be kneaded 

 between the fingers like wax, and on cooling presented the same appearance as to fracture, 

 &c, as before. Tested for nitrogen by Lassaigne's method, and for sulphur by fusion with 

 nitre and caustic potassa, affirmative results were obtained. 



In an examination for volatile matter, one gramme gave 0.5355 vol. matter, 04435 

 coke, and 0*001 of reddish ash, which corresponds to a per centage of 



Coke, . . . 44-35 



Volatile matter, . . 55-55 



Ash, . . . 0-10 



10000 



The coke, which was very porous, was burned off by a slow current of oxygen intro- 

 duced into the platinum crucible. A portion of the asphalt in a Hessian crucible with 

 luted cover, was placed in a wind furnace, and the heat gradually raised to full redness, 

 at which it was kept for some time. The coke thus obtained was of light gray metallic 

 appearance, and exceedingly porous, and throughout its mass exhibited laminae, concentric 

 to the sides of the crucible, like the coats of an onion. A portion of the asphalt was 

 melted by the following process. It was introduced into a Florence flask, to which was 

 adapted a long bent tube for the purpose of condensing and collecting the products of dis- 

 tillation, and placed over a gas lamp; the temperature was carefully and gradually raised. 

 At first white fumes burning with a bright light made their appearance, which were not 

 condensed by the application of cold water. After these, the naphtha came over, with the 

 odour of mineral naphtha, and also somewhat resembling the odour attending the distilla- 

 tion of stearic acid. The asphalt in the flask broke up into smaller pieces, which con- 

 tinued to separate until they became of the size of a small pea; they then fused together 

 and formed a perfectly liquid mass, with gentle ebullition, and of the consistency of mo- 

 lasses, or even more mobile. Some of this poured out into a broken flask, solidified, and 

 when cold, presented a fracture like that of the original substance, but somewhat less bril- 

 liant, and which, though quite hard, appeared more impressible to the nail than before 

 fusion. This experiment was performed twice upon the asphalt which was obtained at the 

 Philadelphia Gas Works.* In each case, just before liquefaction, a white sublimate con- 

 densed in that part of the tube nearest to the flask. It appeared crystalline and soluble 

 in water; though the re-action was less apparent, owing to the small quantity, and to its 

 being impure from condensed naphtha. Rammelsberg (1st supplement Handworterbuch 

 des Ch. Thcils, der Mincralogie) notices an asphalt from Murindo, Columbia, which accord- 

 ing to Mill, contains much Benzoic acid, which can be obtained by alcohol, or by sublima- 



* The second experiment was performed upon part of a specimen from the Philadelphia Gas Works, which 

 had been put away and labelled in my cabinet. It was performed to avoid all chances of error. 



