3^7 



The second fraction had — 



Specific gravity at y-|° C. = 0-8603 



Rotation (7b = +20-4° 



Refractive index at 17° C. ... ... = 1-4763 



The portion remaining in the flask had — 



Specific gravity at x|° C. ... ... ... — o-86io 



Rotation «„ =^ +38-6° 



Refractive index at 17° C. ... ... — 1-4791 



These restilts indicated that the oil consisted principally of one constituent, 

 and that that was pinene. 



The nitrosochloride was readily prepared with it, and this, when finally 

 precipitated from a chloroform solution by methyl alcohol, melted with decom- 

 position at 108° C. The nitrolbenzylamine compound was prepared with the 

 nitrosochloride in alcoholic solution in the usual way, and after finally crystallising 

 from alcohol, it melted at 123-124° C. It is thus shown that the essential oil in 

 the oleo-resin of Agathis rohusta consisted almost entirely of pinene. That a 

 small amount of another body was present was indicated by the slight differences 

 in the physical properties of the several fractions, but it is evident that this 

 constituent, whatever it may be, could only be present in a very small amount. 

 The sylvestrene reaction was not obtained. 



Free Acids. 



The distilled water from which the floating oil had been separated was 

 filtered through wet paper. It measured 950 c.c, and was strongly acid to litmus. 

 100 c.c. required 7-4 c.c. decinormal NaOH to neutralise, or the 950 c.c. would 

 require 70-3 c.c. The water, therefore, contained 0-422 gram volatile acids 

 considered as acetic, or 0-1055 per cent. 



The remainder was neutralised with barium hydrate solution, evaporated 

 to dryness, and heated to 100-105° C. ; 0-158 gram of the barium salt gave 0-1382 

 gram barium sulphate, equal to 87-47 per cent. Acetic acid was proved to be 

 present and butyric acid strongly indicated, so that if the volatile acids con- 

 sisted of acetic and butyric alone, they were present in the proportion of 76-3 per 

 cent, barium acetate, and 23-7 per cent, barium butyrate. 



The Gum. 



The aqueous portion when removed from the solidified resin in the flask, 

 was filtered as clear as possible, evaporated down, the gum precipitated with 

 alcohol, and the precipitate spread on glass to dry. Although colourless at first, 

 it soon became dark coloured on drying, until at last the fully air-dried gum was 

 quite black, and had a very glossy surface. The filtrate from the gum precipitate was 



