PREFACE 



No practitioner who wishes to do his best for his patients and 

 to promote his own interests can afford to neglect any means of 

 cHnical investigation which may help him to arrive at a correct 

 diagnosis, and offer hints as to prognosis and treatment. Pre- 

 eminent among the more recent methods of investigation are those 

 which are applied by the bacteriologist, and it is no exaggeration 

 to say that in many of the infective diseases a diagnosis which is 

 made without a bacterioscopic examination is either mere guess- 

 work or can only be made so late that the patient has suffered 

 unnecessarily in health arid the practitioner in prestige. In many 

 cases, however, the investigation requires a considerable amount 

 of technical skill and access to a well-equipped laboratory. The 

 former may, perhaps, be possessed by the rising generation (for 

 bacteriology is now an integral part of the medical curriculum), 

 but it would be unfair to expect every medical man to add the 

 latter to his already expensive equipage. But in many cases the 

 diagnosis can be arrived at by very simple means — a few slides, 

 cover-glasses, and stains, a good microscope (which ought to be 

 considered as essential as a stethoscope), and a very moderate 

 amount of technical skill, will often enable the practitioner to 

 arrive at a correct diagnosis in a very short time. This little book 

 is intended, in the first instance, to show exactly when this may be 

 done, and to provide clear, succinct, and full descriptions of simple 

 methods which may be employed. The descriptions of the opera- 

 tions which the practitioner can carry out for himself are mostly 

 written in the imperative mood, and are intended to be referred to 

 constantly and carried out, step by step, during the process. They 

 represent the instructions which would be given by a teacher when 



