1JJO 



taken the fraction boiling at 223 (Wurtz) or 226 (Kolbe), it would 

 have yielded the same results. This point is now under examination. 



The formula 



C 16 H 18 =4 vols., 



corresponds not only to butyl, but also to the hydruret of caprylyl, 

 and, of course, both these bodies have the same vapour density ; but 

 several circumstances lead me to believe the hydrocarbon I have 

 obtained to be the radical of the butylic alcohol. The density of the 

 fluid, and the temperature at which it distils, are also rather in 

 favour of this view. It will be seen that 247 F. should be the 

 boiling-point of butyl if Frankland's determination of that of amyl 

 be correct, and Kopp's law hold with these bodies. 



A careful study of the papers already published on the radicals of 

 this series, shows that more than one anomaly appears to exist in 

 their physical properties, the gradations usually observed [in homo- 

 logous groups not being so distinctly marked as with most others, 

 and this fact somewhat impedes their identification. The large 

 quantity of substance which becomes at our disposal from the source 

 mentioned, will, by facilitating the study, throw light on these points. 



I believe I shall be able to isolate at least four of the radicals, viz. 

 propyl, butyl, amyl, and caprotyl, from the coal distillate. The 

 per-centage composition varying so little with the different homo- 

 logues, I rely chiefly on vapour density and products of decomposi- 

 tion as the means of proving their presence. 



The hydrocarbons accompanying the radicals are also quite distinct 

 from the benzole series, as shown by the low density of the nitro- 

 compound. The latter is extremely difficult of reduction by sulphide 

 of ammonium or protacetate of iron, but it furnishes a volatile oily 

 alkaloid by distillation with an alcoholic solution of potash. 



The tedious purifications and the numerous operations required 

 before the substances can be obtained in a state of sufficient purity 

 for analysis from the coal distillate, will probably cause a consider- 

 able period to elapse before a detailed account of all the bodies can 

 be published. 



