226 



But we have found that the foregoing are by no means the only 

 hydrocarbons separated by sulphuric acid and nitric acid, and we 

 hope to establish the existence of other series containing terms iso- 

 meric with, but differing in properties from, benzol and its homo- 

 logues ; we have, moreover, good reason to suspect the presence of 

 other compounds even less linked with the benzol series. 



Action of Reducing Agents on the Nitro-compounds. 

 In order to throw further light on the constitution of the hydro- 

 carbons in Burmese naphtha, removeable by the before-named acids, 

 we have submitted the several nitro-compounds to the action of 

 reducing agents. As was to be expected, our nitrobenzol yielded an 

 abundant supply of aniline when distilled with acetic acid and iron 

 turnings, thus confirming the existence of benzol beyond all possible 

 doubt. In a similar manner the presence of toluol was further esta- 

 blished by the preparation of nitrotoluol and toluidine. Bechamp's 

 method was, however, not equally applicable in all cases, so that 

 Zinin's original sulphide of ammonium process was resorted to ; by 

 its means we have obtained several new bases, and among them one 

 crystallizing beautifully in long needles, having the appearance and 

 colour of alizarine. Some time must however elapse before the great 

 number of new bodies can be fully studied. 



Hydrocarbons not acted upon by Sulphuric and Nitric Acids. 



The hydrocarbons which resist the action of monohydrated sul- 

 phuric and nitric acids form, as has been before stated, by far the 

 larger portion of the distillates obtained from Burmese naphtha. 

 When purified by washing from adhering acid, by fractional distilla- 

 tion, and finally by rectification in a current of dry hydrogen gas over 

 the liquid alloy of potassium and sodium, they are obtained almost 

 inodorous and perfectly colourless. Thus purified, they are very 

 fluid, and retain their fluidity even in the intense cold produced by 

 a mixture of solid carbonic acid and ether. No absolute fixity of 

 boiling-point could be obtained in any of the products ; nevertheless 

 a much greater constancy in this respect was observed than with the 

 hydrocarbons before treatment with strong acids. The lowest boiling- 

 point obtained was 50 C. (122 F.) ; the highest, being far beyond 

 the range of the mercurial thermometer, was not ascertained. The 



