12 MODEKH DAIRY PRACTICE. 



stated as a characteristic of bacteria, as well as of all other 

 living organisms, that they shun certain chemicals which 

 either arrest their growth or entirely destroy them. These 

 materials are called either disinfectants or antiseptics. 

 Further information concerning the disinfectants especially 

 adapted for use in dairy practice will be found later on in 

 this work. 



Bacteriological Methods of Investigation. We cannot 

 here enter into a detailed account of bacteriological meth- 

 ods of investigation. It may be proper, however, to explain 

 briefly the nature and general characteristics of these 

 methods, in order that the discussions entered upon in the 

 body of this book may be more easily understood by per- 

 sons not familiar with bacteriological science. Those in- 

 tending to study in a more systematic manner the rela- 

 tions dwelt on, are referred first of all to the splendid 

 text-books : C. J. Salomonsen's " Bakteriologisk Teknik for 

 Mediciner," published in 1889, and Hueppe's comprehen- 

 sive work, " Die Methoden der Bakterienforschung," 1889. 

 An interesting and plain presentation of the subject is 

 given in the Swedish language in Prof. Curt Wallis' book, 

 " Bakteriologi " (1888).* 



* The following is a list of the more important works on Bac- 

 teriology in the English and German languages, besides those men- 

 tioned above: 



STERNBERG. Manual of Bacteriology. New York, 1892. 



ABBOTT. Principles of Bacteriology. Philadelphia, 1892. 



FRANKEL. Text-book of Bacteriology, tr. by Linsley. New 

 York, 1891. 



MIGULA. Practical Bacteriology. London, 1893. 



JORGENSEN. The Micro-Organisms of Fermentation. London, 

 1893. 



WOODHEAD. Bacteria and their Products. London, 1892. 



