I 10 ANIMAL EXPERIMENTATION 



laboratories in connection with the hospitals, in which not 

 only are methods of diagnosis carried out which cannot be 

 made at the bedside, but in which disease is studied with 

 the view that the knowledge gained can be utilized by 

 others. In the work of the laboratory animal experi- 

 mentation is necessary. The inoculation of animals with a 

 disease often affords the earliest and the surest method of 

 diagnosis, and in some cases it is the only one. The treat- 

 ment of the sick is directly dependent upon the diagnosis, 

 and it often happens that an early and certain diagnosis 

 makes the difference between life and death. The hospital 

 records contain many cases which show that the lives of 

 patients have been saved by methods of investigation which 

 could only be carried out in the laboratory and in which 

 animal experimentation has been utilized. 



In teaching pathology, animal experimentation is neces- 

 sary. The student must see things and not be simply 

 told about them. He must see not only what lias taken 

 place, but what is taking place. The changes in the 

 circulation which form a great part of the phenomena 

 of inflammation can only be understood by study of the 

 circulating blood in the web of the frog's foot. He can 

 only understand anatomical changes by observing the 

 stages of their formation. He must himself inoculate ani- 

 mals and see the development of disease. 



There are two considerations which show especially well 

 the importance of animal experimentation in acquiring 

 knowledge of disease. This knowledge has advanced more 

 rapidly in the last fifty years than in the previous five 

 hundred. It is only in the last fifty years that the methods 

 of investigation which are used in all natural sciences have 

 been applied to medicine. 



These methods are observation and experiment. 



It might be possible for an individual to retire into a 

 cave in the desert and write poetry, or even evolve a system 



