6 



Teniently performed by an easily soluble fixed alkali, such as caustic soda, 

 it will be found, if the alkali, be used with caution, that a gradual 

 disappearance of the fixed alkali takes place as the heating progresses. 

 In this respect it is instructive to compare the behaviour of the two in- 

 dicators phenol-phthalein and litmus; the former shewing us the 

 gradual disappearance of the fixed alkali, while from the behaviour of 

 the latter, we should imagine that the fixed alkali was still present in 

 excess. That this is not so can also be proved by distilling the liquor, 

 when the distillate will be found to behave exactly the same towards 

 the two indicators, blueing litmus and having no effect on phenol- 

 phthalein — due of course to the setting free of volatile organic bases; 

 which have no effect on phenol-phthalein : it need hardly be said that 

 this is not due to the liberation of ammonia. But whatever conclusions 

 may be ultimately arrived at as to the exact nature of the chemical 

 changes, and as to the nature of the products of such decompositions, it 

 will not I think be denied by anyone who carefully goes into the matter 

 that the tempering of the liquor in the Boiling H ouse has a very decided 

 influence on the aroma of the Rum. No one who examines the residues 

 which result from the chloroform and ether extractions of cane juice, be- 

 fore and after the treatment with lime, can have a doubt of this while an 

 examination of almost any rum, which has been manufactured in this 

 country, using the aforementioned solvents, will enable him to discover 

 the same smelling substances which can be extracted from treated cane 

 juice. It is not of course contended that the whole of the aroma of Rum 

 is due to this cause, but I do not hesitate to say that directly and in- 

 directly a very considerable part of it is. And moreover in breaking 

 fresh ground, as I believe I am in these researches, it was considered 

 more important to attempt to localise the chief points of interest and 

 to ascertain the actual facts of the case, rather than to dwell on the 

 theoredcal side of the question, which becomes of importance only in 

 relation to facts. These researches too were commenced in the first 

 instance with one object in view, viz to elucidate he nature of the 

 action of No. 18 yeast in producing its characteristic aroma. I very 

 soon found that I was working in the dark on this very interesting 

 question, and it is only now on having learnt the nature and the result 

 of the action of temper lime on cane juice, that I am encouraged to be- 

 lieve that I have found the solution of this previously difficult problem. 

 But of this more anon. It is obvious however that even the practical 

 side of the question is far from being exhausted, and an ever broadening 

 field of investigation is opened up. If one may be allowed to theorize 

 a little, there seems sufficient grounds for concluding, from the results 

 which I have up to now attained, that though the aroma of rum is in 

 the first instance derived from the soil, that this influence is chiefly 

 potential not actual ; that it is latent, dormant, and only brought into 

 existence during the process of manufacture. If this should prove to 

 be the case, it would seem to hold out a hope that much may be done to 

 improve our rums both for the home trade in England and for export 

 to Germany ; and to imply a rebuke against niuxi^uiing with folded 

 hands — " it's the soil that does it" 



