SECTION 11. 



Under tliis section it is proposed to glance at some topics 

 whicli may with equal propriety be regarded as belonging to 

 the ' Theory or Science of Medicine ' as to the ' Practice,' but 

 a slight knowledge of which is very necessary ere the detailed 

 description of disease is entered upon. 



CHAPTER I. 



NOSOLOGY ; OR, THE DEFINITION, NOMENCLATURE, AND 

 CLASSIFICATION OF DISEASE. 



In following out the limited but large subject, the ' Practice of 

 Equine Medicine,' it will be found necessary both for the sys- 

 tematizing of our knowledge, and for the concentration of our 

 facts and observation, as also as a ready means of access to 

 what we have obtained, that we should follow to some extent 

 at least the ordinarily recognised lines and principles upon 

 which is constructed the ' Nosology ' of the present day. 



The diseases which engage the veterinarian's attention re- 

 quire to be defined and distinguished, both individually and 

 as associated in groups. They must be named, so that both as 

 individuals and divisions they may be recognised and distin- 

 guished from other individuals and groups ; and they require 

 for convenience' sake, at least in their examination, to be rele- 

 gated in classes, orders, and species. 



The defining, naming, and classifying of diseases, embracing 

 and making up the department of nosology, have been carried 

 out at different periods of the history of medicine on very 

 varying and different principles. 



The idea enunciated by Sydenham and carried out by Sau- 

 vages, that diseases, like animals and plants, might be most 



