INTRODUCTORY. 



All animals from early youth to old age are exposed to niairy 

 dangerous and troublesome affections, the result, of causes not 

 less complex and multifarious than those influencing the human 

 organization. Many diseases are the consequences of domesticity 

 and of defects inherited from progenitors; others are dependent 

 upon accidental circumstances, had treatment, and improper 

 nourishment. Xot a few mortal maladies are the result of con- 

 tagion, infection, and other like causes. While all domestic 

 animals are more or less subject to certain diseases pecidiar to 

 their race, those breeds of most value to man are liable to a 

 greater number of ills aird casualties than others, for the reason 

 that they are frequently exposed to extraordinary fatigue. Those 

 diseases resulting from specific causes, either natural to the race 

 or artificially produced by the animal itself in a state of morbid 

 derangement, are most frequent and fatal. The close resem- 

 blance existing lietween the diseases of the lower animals and 

 those of the human race, as also the strong similarity in the action 

 of many drugs over the brute and human systems, render the 

 study of one branch almost synonymous with that of tiie-other. 

 It has been strenuously objected that drugs do not act upon the 

 lower animals in tlie same manner as upon man. Stated in its 

 broad sense, this is not true. In the vast majority of cases the 

 action of drugs upon man ant! upon the lower animals, though 

 seemingly different, is in reality similar. The more knowledge 

 we acquire the fewer exceptions remain unexplained, and the 

 whole matter is in all probability sul\ject to laws whose develop- 

 ment will greatly aid in explanation of various obscure clinical 

 phenomena. 



In the large cities of our country and in England hospitals 

 for the accommodation of invalid animals are conducted upon 



(5) 



