3$6 Royal Society, 



tities than bones and other animal substances ; but as both bones and 

 coal are distilled on the largest scale for commercial purposes, their 

 crude oils may be easily procured in any quantity, and from these 

 their respective series of bases may be readily prepared. In regard 

 to the bases from beans and other seeds, the case is quite different ; 

 as the scientific chemist is compelled to distil these substances on 

 purpose, an operation which cannot be conveniently conducted in a 

 laboratory, as it requires an apparatus so large as to be almost upon 

 a manufacturing scale. 



Oil-cake. — As the Phaseolus commimis was regarded as the type 

 of the Leguminosie, oil-cake, or the expressed seeds of L'mum usita- 

 tissimum, was selected from that numerous class of plants in which 

 the starch of the Graminese is replaced by oil. The products of its 

 distillation were very similar to those from beans, containing how- 

 ever more ammonia and a somewhat smaller proportion of oily bases, 

 which, though similar, appeared to differ from those of the pre- 

 ceding series. They were also equally devoid of aniline. 



Wheat, Triticum hybernum, and subsequently peat from the 

 neighbourhood of Glasgow, were also destructively distilled. Both 

 of these substances, in addition to ammonia, yielded a series of oiiy 

 bases, which also contained no aniline. 



Distillation ofviood, — The author proceeds to state, that through 

 the kindness of an extensive pyroligneous acid manufacturer he 

 "was enabled to examine considerable quantities of the crude acid 

 liquor obtained from the destructive distillation of beech, oak, and 

 other hard woods. The stems and larger branches of trees are alone 

 employed for this purpose. He found to his surprise that this acid 

 liquor contained scarcely a trace of ammonia or of any other organic 

 base, showing that the woody portions of the limbs and stems of 

 trees are nearly devoid of nitrogenous matter, in which respect they 

 differ extremely from peat, which in general contains two per cent, 

 of nitrogen ; and he considers this circumstance as perhaps calculated 

 to throw some light upon the origin of the coal-beds, Avhich some 

 geologists believe to have been formed from the submersion of 

 forests and the floating of uprooted timber into estuaries and lakes, 

 while others contend that they have been produced by the submersion 

 of beds of peat. Irrespective therefore of other considerations, the 

 author urges in favour of the latter opinion, that wood is not capable 

 of furnishing the amount of nitrogen we find existing in coal, while 

 peat contains rather more than double the quantity required. The 

 expectation of procuring aniline, picoline, &c., the coal series of bases, 

 from the distillation of peat, was disappointed ; a result only to be 

 accounted for on the hypothesis, that the different genera of plants, 

 when destructively distilled, yield different series of organic bases. 



From the facts which have pi'eviously been stated, the author con- 

 siders himself warranted in concluding that when ammonia is pro- 

 duced by the destructive distillation of either animal or vegetable sub- 

 stances, it is always accompanied with the formation of organic 

 bases. Now as ammonia is known to be procurable from these sub- 

 stances by other methods than destructive distillation, it seemed 



