370 Mr. E. M. Corner and Dr. J. E. H. Sawyer. [Apr. 4, 



are not worn out by work under a prolonged strain. And, as has been 

 pointed out above, if the disease should be of long duration, a fall of 

 temperature rather than a rise would be expected to occur. The 

 reason for this supposition is that as death approaches in long illnesses, 

 there must presumedly be a considerable diminution of heat production, 

 which is not counter-balanced by the small reduction of the heat lost 

 at the surface. The investigations in the first part of this paper 

 support these ideas, since they seem to show that rises in the bodily 

 temperature occur more frequently in short diseases, and falls of 

 temperature in those of longer duration. 



The animate factor in pyrexia is chiefly that of the action of the 

 central nervous system. " The nervous system exercises a control 

 upon the loss of heat by means of the vaso-motor system, which 

 regulates the amount of blood in the deep and the superficial parts of 

 the body, and by the respiratory centre which controls the frequency 

 and depth of respiration ; upon the production of heat through the 

 nerves which control the activity of the tissues, chiefly the muscles."* 

 The heat production in a tissue is probably not under the control of 

 that tissue itself, but its thermogenetic function is governed by its 

 proper segment of the spinal cord. The nervous centres cannot of 

 themselves produce heat ; they can only govern the manufactories. 



As the brain centres exercise a tonic control over the spinal centres 

 which are in connection with the reflexes, sphincters, etc., so, in a 

 similar manner, the higher centre or centres of the brain may hold in 

 check the lower centres in the spinal cord, which give the tissues their 

 power of heat production. The brain centres are the last to be evolved 

 in the history of animal life, and it may be urged that they are the 

 most complex, and therefore the most easily thrown out of gear. For 

 this reason a generally acting death agent, such as a toxic condition, 

 will affect and inhibit the action of the higher centres before or to a 

 greater degree than it will damage the lower. Whenever the higher 

 centre is cut off from the lower, the latter becomes exaggerated in its 

 action. This is well seen in the spastic condition when the reflexes 

 etc., are exaggerated. In a similar way, with the commencement of 

 dissolution of the higher centres, a death elevation of temperature may 

 be expected to result. 



The fallacy in reasoning from the above analogy is that, in the one 

 case, the facts deal with a reflex centre, and in the other, as far as is 

 understood, with an automatic. How t far these differ in regard to 

 their relation to the higher centres, it is impossible to say, but one 

 can instance the acceleration of the automatic and rhythmic centre 

 of the heart when the inhibitory control of the vagus is cut off. 



An important fact which this investigation shows is that, as death 

 approaches, there is a tendency for a sudden rise in the bodily 



* Pembrey, Schafer's ' Text-Book of Physiology,' 1S98, vol. 1, p. 854. 



