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NOTES ON PROF. JORGENSEN'S "MICRO-OR- 

 GANISMS OF FERMENTATION." 



By Percival H. Gkeg. 



During the last ten years a great reform has been effected, . 

 and is still working its way, among those industries in which the 

 activity of Micro-organisms plays an important part. 



The essence of this reform consists in the recognition of an individual- 

 ity among cellular organisms of an apparently similar structure ; while 

 the reform itself is the perfection of those methods of isolation 

 and subsequent cultivation of these organisms in a state of absolute 

 purity by which this individualism has come to be recognised as an 

 established fact. 



In no other industries has such a reform been effected as in the arts 

 of Hrewmg and Spirit-making. To give a comprehensive review on the 

 most salient points of the system of fermentation by pure yeast as 

 originated by Pros Emil Christian Hansen of Copenhagen ; to furnish 

 an important and convincing testimony of the great practical benefit to 

 be derived from the introduction of the reform into the Brewing and 

 Spirit industries all over the world ; and finally to form a manual of in- 

 struction not only for the Student, the Chemist, or the Physiologist, but 

 also for the practical Brewer and Distiller, in the science of Fermenta- 

 tion, is the aim of the " Micro-organisms of Fermentation" by Alfred 

 Jorgensen of Copenhagen. 



This book which has now passed into the 3rd edition in the Grerman, 

 and into the 2nd in the English language, besides being we hear in the 

 course of being tr mslated into French, comprises about 230 pages 

 (German Edit.). It is profusely illustrated and furnished with a complete 

 index, and is divided into six chapters. Chapter I. treats of the methods 

 employed in the preparation of absolutely pure cultivations, of the 

 sterilisation of instruments, apparatus, of liquid and solid nutrient- 

 media. Chapter II. treats of the methods to be employed in the 

 examinations of the Micro-org misms suspended in air and water, with 

 special reference to aerial contamination in Breweries. Chapters III, 

 and IV. on the most c mrnionly occurring forms of Bacteria, Moulds, 

 Mucors, etc. Chapter V. which is the longest in the book and in which 

 the greatest interest will probably be awakened, is concerned with the dis- 

 cussion of the true alcoholic ferments. Chapter VI. which contains a 

 special description of the two machines devised by Hansen & Kiihle 

 and Jorgensen & Bergh, for the introduction of pure yeast on a large 

 scale into Breweries & Distilleries, concludes with a review of the 

 reception accorded to Prof. Hansen's system by eminent Technologists, 

 and the practical results attained in the large breweries and Distilleries 

 in Europe. 



I cannot too earnestly recommend this book to the very careful 

 consideration of all those interested in the manufacture of Jamaica 

 Rum. From what I have seen of the system of Fermentation 

 practiced in Distilleries in this country, I am convinced that much 

 may be done, with comparatively speaking small expenditure, to 

 improve not only the quantity of spirit from a given volume of wash of 

 & given saccharine strength, but also to improve the quality of the 



