A STUDY 1 i\ MORBID AND NORMAL R II Y S I L O G Y. 05 



Heat Production 

 Before Section 



Loss of heat from bodily reserve none. 



Hourly heat dissipation = hourly heat production 184.8352 



After Section. 



Fall of bodily temperature in \{ hours 2.7'J, in 1 hour 2.232 = t. 

 Q= \V X t X sp. h. = 10.25 X 2.232 x 0.75 = 27.2025 = loss of heat IVuni reserve. 

 Hourly dissipation of heat 129.1425 

 Loss of heat from reserve 27.2025 



Hourly production of heal 101.04 

 Summary. 



Hourly production of heat before section 184.8352 



Hourly production of heat after section 101.94 



DimintUioH of heat pro<lHr/io7i foltowimj section 82.8952 



When the mecluUa is injured in such a way as to paralyze the vaso-niotor centres, 

 thermic symptoms similar to those caused by section of the cord would natujally 

 be looked for. In Experiment 54 such symptoms were actually present, the heat 

 dissipation being primarily increased and the heat production dirainislied. On the 

 other hand, in Experiment 55 the result was not altogether in accord with the 

 preconception. Heat production certainly was diminished, but heat dissipation so 

 far from being increased was actually lessened. The medulla was not, however, 

 completely severed, one-half of it indeed being uninjiu-ed. It is, therefore, very 

 probable that the vaso-niotor paralysis was not complete, sufficient of the nerve 

 fibres remainmg intact to allow of some regulation of heat dissipation by the 

 organism. That increased heat dissipation follows immediately upon complete 

 vaso-motor palsy is very strongly indicated by the immediate and very rapid fall 

 of bodily temperature which occurred in Experiments -44 and 45 when the knife 

 was plunged into the vaso-motor centre. 



From all the evidence it seems to me that we are justified in concluding that 

 wounds of the medulla so situated as to paralyze the vaso-motor centres cause decreased 

 heat production vith (certainly sometimes and probably always) j^rininrili/ increased 

 heat dissipation. 



The next series of experiments were directed to the determination of the effect 

 upon calorification, of section of the medulla at its junction with tlie pons. The 

 experiments are as follows : — 



Experiment 56. 



