PREFACE. 



It has been my good fortune to be so situated during the past few years 

 that my entire time has been devoted to the study of histology and micros- 

 copy, with special reference to the microscope in its relation to the practice 

 of medicine. 



Each year has accumulated the proofs that a good knowledge of the use 

 of the microscope is of the first importance to the student of medicine, 

 whether an undergraduate, or a practitioner in private or hospital practice. 



Two reasons are generally given by our physicians as excuses for their 

 ignorance of this important branch; lack of skill in the manipulation of the 

 instrument, and the great outlay of time and money. 



It is a fact that our busiest practitioners are the ones who give the pro- 

 fession the most knowledge through the press. It is also a fact that among 

 these same men are found those who t do so much work with the micro- 

 scope. 



I am convinced that those physicians who do not use the microscope 

 are either totally devoid of any desire to advance in their profession or are 

 lacking the necessary qualifications to enable them to appreciate the useful 

 and practical. 



I hold the great majority of the medical colleges of this country directly 

 responsible for the lack of this love for scientific research. They seek to please 

 the students by prejudicing them against the scientific investigation of disease; 

 and the students become practitioners before they are aware of their ignorance 

 of matters that should have been familiar to them during the term of their 

 pupilage. A few strong men are commencing to express themselves in 

 favor of microscopic inquiry, but to the coming physician must we, as 

 microscopists, look for a solution of the more exact nature of disease and 

 the more effective methods for its prevention and cure. 



Scientific work does not unfit a man for practical work, and I take the 

 liberty to prophesy that the physician of the future must be a scientific man 

 or he will not be called a practical man. 



I believe I show in the first part of this work that the microscope is 

 not only eminently useful but also absolutely necessary for the correct diag- 

 nosis of certain, not uncommon, forms of disease. 



A careful study of the first chapter will enable any one of ordinary 



