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fermentation of a previously known character in comparison to working 

 with mixtures of unknown yeasts, present in unknown and varying 

 proportions, as would be the case if we started our No. 1 

 vat with cane juice, instead of yeast from the apparatus, I have 

 enlarged on in the earlier portion of this paper, and I can only add 

 that the surest way to attain perfection in a manufacture which 

 is; admittedly subjected to unaccountable and unlooked for changes, 

 lies, in the elimination of the uncertainties, .unknown quantities and po- 

 tential causes of variation as far as lies in own power, It might 

 therefore be possible by the selected yeast system working in conjunc- 

 tion with the " trash" cistern or working by itself not only to obtain a 

 greater control over the progress of our fermentations to make 

 "quality" rum at a less sacrifice of time and material, but to alter the 

 character of the resulting rum to a certain extent at will. Thus further 

 search might reveal the presence of other aroma producing germs be- 

 sides No. 18. We mightt herefore in the future be able to produce an 

 aromatic rum by a pure fermentation of 18 yeast or some other aromatic 

 germ without the trash cistern. Again we might set to and manufac- 

 ture an aromatic rum by means of No. 18 yeast working in conjunction 

 with the trash cistern, or again a different charactered rum by any of 

 yeasts No. 1, 4, 5,7, 8, 14, 17 or 19 working in conjunction with the 

 trash cistern according to circumstances. So muchf or the case where 

 it is desired to produce an aromatic rum. With regard to the produc- 

 tion of common clean rum it would seem as if the introduction of a se- 

 lected yeast giving a rapid attenuation and big yield could not fail to be 

 of great service. It might prove of great value in producing a purer 

 and more even charactered rum containing less bye- products which 

 might be fit for speedier or direct consumption and by this means the 

 consumption might be stimulated. 



As to this and all other questions raised in this paper I would impress 

 up on those whom these matters may concern, that mere theorising 

 is of no use at all. Laboratory experiments are indispensable in 

 shewing whether there is an a priori possibility of an improvement 

 being effected or a reform carried out in these matters, but the deciding 

 word can only be spoken after systematic experiments in the Still House it- 

 self have shewn whether the reform is practically possible. At the same 

 time I am of opinion that much may be done in Jamaica Still Houses, and 

 this is a very important point in these days, at a very much smaller ex- 

 penditure of money than would be required to effect an equal improve- 

 ment in our Sugar manufacture. In the old days when the sugar crops 

 were smaller in proportion to the working capacity of the Still houses, 

 " spontaneous" fermentation could be trusted to do the work, but now- 

 a-days, owing to the sugar crops having increased, a great many estates 

 habitually run their liquors before they are " dead" and the consequence 

 is an inferior product all round, is put on the market ; and the consump- 

 tion of rum, though certainly not exclusively owing to this cause, has de 

 creased. Greater demands therefore are made on the fermentating agent, 

 i.e, on the yeast, and therefore greater attention and care must* be bes- 

 towed on the yeast question than has hitherto been bestowed. 



