SECTION III. 

 PRINCIPLES OF STERILISATION AND PURE CULTIVATION. 



CHAPTER X. 



METHODS OF STERILISATION. 



71. Sterilising. 



To sterilise an object, e.g. a nutrient solution, piece of apparatus, &c., means to 

 treat it in such a manner that it no longer contains any living germs, and is 

 therefore sterile. 



The reader must not expect to find in the present work a detailed description 

 of even the most important of the methods of working adopted for this purpose. 

 Those who have an opportunity of studying the methods of Technical Mycology 

 in a laboratory devoted to Fermentation Physiology will learn all they need 

 much more speedily and intelligibly from oral instruction than from a printed 

 book. On the other hand, those who have access to the latter only will attain 

 their object by the exertion of a little diligence in consulting the books referred 

 to later on, and especially 



Hueppe, Ferdinand : Die Methoden der Bakterien-Forschung, 5th edition, 1891, 

 Wiesbaden (C. W. Kreidel). 



Lindner, Paul : Mikroskopische Betriebskontrolle in den Garungsgewerben, 

 1895, Berlin (P. Parey). 



In the first-named compendium the reader will find a better description than 

 the present author could give of all the methods used in general Microbiology. 

 The second, very useful, work treats, with great experience, a narrower field, 

 wherein it will afford reliable guidance and help to the student on all matters 

 relating to fermentation technology. In the newest edition (1895) of the work 

 on water-analysis by TIEMANN-GARTNER (I.), already referred to (and which 

 should be in every efficient chemical laboratory), the reader will also find 

 descriptions of the most important manipulations and methods employed in 

 sterilisation, pure cultivation, re-inoculation, &c. In selecting apparatus for 

 installing a new laboratory for Fermentation Physiology work, the beginner 

 should seek the advice of an expert, and should compare the illustrated catalogues 

 of such firms as make the supply of these appliances a speciality, e.g. U. Desaga, 

 of Heidelberg ; Erhardt and Metzger, of Darmstadt, &c. 



It is not our purpose now to give a detailed initiation into the work of a 

 fermentation physiologist's laboratory, but rather to describe, in bold outline, 

 only so much as is necessary to facilitate the object of the present work, viz., the 

 study of the character and modes of action of the organisms of fermentation. 



72. Freeing the Air from Germs. 



There are two chief methods by which liquid substances and gases can be 

 sterilised, viz., either by killing the germs present therein, or by removing them 



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