54 



SCIENCE 



[N. S. Vol. XXXIX. No. 993 



essay form a review of his findings, which 

 he may be called upon to read before the 

 class, and which is then discussed by the 

 other students, with the object of bringing 

 out the variations that occur, and of empha- 

 sizing the chief conclusions. 



The time allowed for these experiments 

 should be about one half of that occupied 

 by the preliminary nerve-muscle work. 



The student may now proceed to the ex- 

 perimental work on mammals, beginning 

 with such problems as the control of blood 

 pressure, the mass movement of blood, and 

 other circulatory problems, and then pro- 

 ceeding with those pertaining to the respi- 

 ratory, digestive, excretory and nervous 

 systems. It is in the conduction of this 

 course that the greatest pedagogic skill is 

 demanded, for the experiments must be 

 most carefully chosen so that their results 

 may bring to light fundamental principles, 

 and so that there may not be unnecessary 

 repetition. The animals employed must be 

 deeply anesthetized, and there must be suffi- 

 cient competent oversight to make certain 

 that at no stage do any of them show the 

 least signs of consciousness. The animals 

 must of course be killed at the termination 

 of the experiment. 



The question is sometimes asked as to 

 whether it is necessary for the efficient 

 training of medical students that they 

 should participate in mammalian experi- 

 ments. In my judgment, the question is as 

 absurd as if it concerned the practical 

 training of engineers. To drive our loco- 

 motives we do not employ men who have 

 merely learned the theory of engine con- 

 struction; we demand such as have gradu- 

 ally acquired a practical knowledge by 

 actual experience. 



It is obviously unnecessary that every 

 student of the class should perform each ex- 

 periment by himself; groups, composed of 

 four or five students, should be formed. 



care being taken that the particular duties 

 of the various members are so controlled by 

 rotation that each has an opportunity dur- 

 ing the course of actually taking part in 

 every technical detail of the experiment. 

 There should also be a sufficiency of 

 trained instructors so that there is approx- 

 imately one of these for every two groups. 

 Conducted in this way, the experiments 

 come to assume in part the nature of de- 

 monstrations, but they are of immensely 

 greater value than the older lecture-table 

 demonstration, because each student, by be- 

 ing an active participator in the work, 

 comes to take a very much greater interest 

 in the bearing of the experiment, besides 

 acquiring greater operative and technical 

 facility, which will be invaluable to him in 

 his subsequent clinical work. 



There are some persons who would doubt 

 the necessity of even demonstrating any 

 mammalian experiments to medical stu- 

 dents. They maintain that it is unneces- 

 sary to rep eat observations that have already 

 been satisfactorily made and recorded. 

 But if this were true for physiology, it 

 must obviously also be true for physics and 

 chemistry. According to those persons, 

 there could be no value in any practical 

 work in the pre-medical sciences, which 

 would mean that the student on entering 

 the wards would be no more familiar with 

 the methods which are at his disposal 

 for the accurate investigation of disease 

 than would be a student of theology or law. 

 "When we bear in mind, however, that a 

 patient with a disturbed blood circulation 

 is strictly the same from the pathological 

 standpoint as an anesthetized animal with 

 corresponding conditions produced experi- 

 mentally, we see how unreasonable such a 

 contention comes to be. Is it better to 

 have the student learn how to control a 

 breakdown in the circulation on the patient 

 or on the anesthetized animal? It is pos- 



