4 A MANUAL OF BACTERIOLOGY 



" He is no better at all." Such people bring un- 

 founded charges of cruelty against those who are 

 striving, to the best of their ability, to lessen the 

 pains of disease both in man and also in animals, for 

 they, like us, are liable to disease, and, like us, they 

 suffer from it.' 1 



Without vivisection, the important researches of 

 Pasteur, Koch, Klein, and others could not have 

 been conducted; in fact, vivisection is absolutely 

 necessary to ascertain the pathogenic nature of any 

 microbe. 



We now proceed to detail the general properties, 

 etc., of microbes. All microbes contain two principal 

 parts a cell-wall or limiting membrane and a 

 semi-fluid contents the protoplasm. The cell-wall 

 is composed of cellulose a carbohydrate having the 

 empirical formula C 6 H 10 5 . The protoplasm ap- 

 pears to vary somewhat in its chemical composition; 

 for, in some microbes, this complex substance is 

 devoid of sulphur and phosphorus, whereas in 

 others, both of these elements are present. The 

 protoplasm which is devoid of sulphur and phos- 

 phorus, has been termed mycoprotein by Nencki, 

 and has entirely different reactions from the proto- 

 plasm containing sulphur and phosphorus. 



Microbes are capable of giving rise to various 

 products, such as acids, alkaloids, colours, enzymes, 

 albumoses, etc. This property depends upon the 

 present potentialities of the protoplasm (in each 

 case), and the inter-relation of its various functions, 

 and these again result from, or are modified by, the 



1 Dr. Lauder Brunton in Nature, vol. xliv. p. 331. 



