1 826.] and NapkthaUne, and on a mw Acid produced, 2dS 



greater part was retained in solution. The diluted fluid being 

 filtered was of a light-brown tint, transparent, and of an acid and 

 bitter taste. 



For the purpose of combining as much naphthahne as possible 

 with the sulphuric acid, 700 grains, with 520 grains of oil of 

 vitriol, were warmed in a Florence flask until entirely fluid, and 

 were well shaken for about 30 minutes. The mixture was red; 

 and the flask being covered up and left to cool, was found, after 

 some hours, to contain, at the bottom, a little brownish fluid, 

 strongly acid, the rest of the contents having solidified into a 

 highly crystalline mass. The cake was removed, and its lower 

 surface having been cleaned, it was put into another Florence 

 flask with 300 grains more of naphthaline, the whole melted and 

 well shaken together, by which a uniform mixture was obtained; 

 but opaque and dingy in colour. It was now poured into glass 

 tubes, in which it could be retained and examined without con- 

 tact of air. In these the substance was observed to divide into 

 two portions, which could easily be distinguished from each 

 other, whilst both were retained in the fluid state. The heavier 

 portion was in the largest quantity ; it was of a deep-red 

 colour, opaque in tubes half an inch in diameter, but in small 

 tubes could be seen through by a candle, or sun-light, and 

 appeared perfectly clear. The upper portion was also of a deep- 

 red colour, but clear, and far more transparent than the lower : 

 the line of separation very defined. On cooling the tubes, the 

 lighter substance first solidified, and after some time the heavier 

 substance also became solid. In this state, whilst in the tube, 

 they could with great difficulty be distinguished from each 

 other. 



These two substances were separated, and being put into 

 tubes, were further purified by being left in a state of repose at 

 temperatures above their fusing points, so as to allow of separa- 

 tion ; and when cold, the lower part of the lighter substance, 

 and the upper, as well as the lower part of the heavier substance, 

 were set aside for further purification. 



The heavier suhstatice was a red crystalline solid, soft to the 

 nail like a mixture of wax and oil. Its specific gravity was 

 irom 1*3 to 1*4, varying in different specimens ; its taste, sour, 

 bitter, and somewhat metallic. When heated in a tube, it 

 fused, forming as before a clear but deep-red fluid. Further 

 heat decomposed it, naphthahne, sulphurous acid, charcoal, &c. 

 being produced. When heated in the air it burnt with much 

 flame. Exposed to air it attracted moisture rapidly, became 

 brown and damp upon the surface, and developed a coat of 

 naphthaline. It dissolved entirely in alcohol, forming a brown 

 solution. When rubbed in water a portion of naphthaline sepa- 

 rated, amounting to 27 per cent, and a brown acid solution was 



