PREFACE. 



In the following pages it has been the Authors' endeavour to place 

 clearly and succinctly before their readers the methods employed in 

 the examination and cultivation of Micro-Organisms, especially of 

 those that are supposed to have any relation to disease. 



Their object in so doing is twofold : first, to supply to the 

 worker in the field of Scientific Medicine a handy guide, to which 

 reference may be made for instruction and details which can other- 

 wise be obtained only from scattered papers and treatises in various 

 languages ; second, to show how extremely simple are most of the 

 methods of research, and thus encourage, as they themselves have 

 been encouraged, young Pathologists to work in a domain, which 

 daily, as it yields new facts to the patient explorer, discloses greater 

 potentialities. , ' 



They know how difficult it is for the busy practitioner to devote 

 time to work which, though simple in its details, requires close 

 and continued attention ; but they would point out that artificial 

 cultures are easily made, that tissues may be readily preserved for 

 examination, and that those who devote themselves to the subject 

 are usually ready to supply the materials for these cultures, and to 

 conduct the further necessary examination. As the writers have for 

 some years been endeavouring to collect material and statistics in 

 connection with the subject of the relations of Micro-Organisms to 



