12. Circumstances are, however, constantly arising which interfere 

 with the equihbrium of these functions, and then a perverted nutritive 

 process is estabhshed, disorder and disease being the result ; hence, 

 health and disease are so intimately blended, like daylight and 

 darkness, that we cannot tell when one ends and the other begins. 



DEFINITION OF TERMS. 



13. Before proceeding further, it will be necessary to note and define 

 certain terms which are in general use in the veterinary profession. 



1. Pathology — Is the study of disease and its locality — the science of 



the nature, causes, and remedies of diseases. 



2. Etiology — Shews the various causes of disease — external, 



internal, mechanical, chemical, climatic, predisposing, 



predisposition, hereditary, exciting, age, sex, &c., &c. 



3. Symptomatology — Gives the various symptoms. Negative and 



Positive. In some cases there are very definite symptoms, 

 whicli indicate clearly the nature of an ailment ; in others 

 the indications are few, and lead to no definite conclusion. 

 In such a case the practitioner resorts to the negative method ; 

 the absence of certain symptoms shows that the malady is 

 not so-and-so. Thus he can exckide certain complaints from 

 being the actual one, until the choice is brought down to a 

 few possible diseases only. The thermometer is of great 

 utilit}' in this department. 



4. Prognosis — Means the prediction of probable progress and result 



of a malady. 



5. Therapeutics — Is the branch of Medicine concerned in the 



treatment and cure of disease. 



6. Hygiene — Treats of Ventilation, Sanitation, Clothing, Dieting, 



Nursing, &c., &c. — in fact all items for the maintenance of 

 health and its preservation. 



