ANOCIATION 249 



is odorless and non-suffocating ; a few inhalations are 

 sufficient to induce unconsciousness ; it is less likely 

 to produce nausea than is ether ; and laboratory experi- 

 ments and clinical experience have shown that by the 



A. B. c. 



Section of normal Section of adrenal of Section of adrenal of 

 adrenal of dog. dog after continuous ad- dog after continuous ad- 

 ministration of ether for ministration of nitrous 

 four hours. oxid for four hours. 



FIG. 60. COMPARATIVE EFFECTS OF ETHER AND OF NITROUS OXID ON 

 THE ADRENALS OF DOGS. 



Note the disappearance of cytoplasm and of some nuclei and the irregular 

 shapes of other nuclei in B as compared with the general conservation of 

 cytoplasm and the well-shaped abundant nuclei in C. 



(From photomicrographs, X 1640.) 



use of nitrous oxid the organs of the kinetic system are 

 actually to a large extent protected against exhaustion 

 from the traumatic impulses of the operation. (Figs. 59, 

 60, 61.) Ether, however skillfully administered, in- 

 duces a period of psychic stress in the earlier stages of 



