AUTHORS PREFACE 



THE present work is intended to furnish the student and 

 the practitioner with a guide to the science of Bacteriology ; 

 consequently the methods of investigation have been dealt 

 with as thoroughly as possible, special attention being paid 

 to the elementary technique. The Author has thought it 

 best to describe the micro-organisms according to the loca- 

 lities in which they are met with, a plan which rendered 

 it possible to go thoroughly into the respective methods of 

 research in their proper places. Particular attention has 

 been given to the pathogenic micro-organisms, and so 

 much the more regard had to be paid to the chemical 

 relations of the life of bacteria, and to their biology gene- 

 rally, that recent events give us reason to hope for an ex- 

 tension of our therapeutic powers from this direction. 



Engravings of the most important bacteria have been 

 provided, showing their form and the appearances pre- 

 sented by their growth. These are intended to serve the 

 reader as models of the typical forms, to which he may be 

 able to adhere in his own investigations. 



The Author has* endeavoured in the text to consider 

 the views of all the different schools, and to this end 



