862 ANIMAL HE A T. 



patients suffering from traumatic section of the spinal cord. The general result 

 is a subnormal temperature so long as the patient's condition is not complicated 

 by other internal or external disturbance. The subnormal temperatures are 

 due to excessive loss and diminished production of heat, owing to the 

 vasomotor and motor paralysis. The section of the spinal cord high up in the 

 cervical region abolishes the power of regulating temperature. When the 

 patient is exposed even to moderate cold, his temperature falls owing to the 

 increased loss of heat and to the diminished production of heat. On the 

 other hand, if the weather be hot and the patient be too well covered with 

 bedclothes, his temperature rises, and may reach a dangerous height, owing to 

 the diminished loss and the increased production of heat in the body. In the 

 paralysed man the production of heat rises and falls with the external tempera- 

 ture. In the case of the high temperatures there are several factors which 

 may play an important part ; the paralysed parts soon cease to sweat ; in fact, 

 Horsley has shown that, by the use of pilocarpine, it is possible to localise 

 the level of the injury to the cord. The respiration is hampered, it is only 

 diaphragmatic ; the ventilation of the lungs is therefore imperfect, and less 

 heat is lost by the cooling of the inspired air, and by the evaporation of 

 water from the respiratory tract to saturate the expired air with moisture. 

 Further, the warmer the paralysed tissues the greater is their metabolism and 

 production of heat. 



It naturally follows that, in cases of section of the spinal cord in the 

 dorsal or lumbar regions, the regulation of temperature is less disturbed. 



The influence of the brain upon the regulation of temperature. 

 It is impossible to state concisely and dogmatically the influence of 

 the brain upon the temperature of the body. With our present know- 

 ledge it is only permissible to review the chief results obtained by 

 various observers, and to draw some provisional conclusions. 



In 1866, Tscheschichin 1 published the results of experiments, which 

 showed that a section between the medulla oblongata and the pons 

 Varolii caused a rise in the temperature of rabbits. In one case the 

 rectal temperature rose in two hours from 39'4 to 42'6, and at the 

 same time there was a corresponding increase in the rate of the pulse 

 and respiration. On the other hand, section of the spinal cord between 

 the third and fourth cervical vertebrae caused, in another rabbit, a fall 

 in temperature from 38'9 to 32'l. From these experiments Tsches- 

 chichin concluded that a moderator centre exists in the brain, and pre- 

 vents the excessive activity of an augmentor heat centre in the medulla 

 oblongata. Lewizky 2 repeated but could not confirm these experi- 

 ments ; he observed a steady fall in temperature after the operation. 

 The subject was then taken up, under the guidance of Heidenhain, by 

 Bruck and Giinther, 8 who, working upon rabbits, obtained positive 

 results in eleven, negative in twelve cases. They found in one case a 

 rise from 39 0- 31 to 42'5 in the rectal temperature, two or three hours 

 after the operation. These observers further found that simple puncture 

 with a probe between the pons and medulla was more effectual than 

 section, and they noticed that the rise in temperature occurred not only 

 in the interior, but also in the peripheral parts of the body, a fact which 

 indicates that the rise is due to increased production of heat. Bruck 

 and Giinther do not agree with Tscheschichin's view of a moderator 

 centre, for they point out that the results can be produced by electrical 



1 Arch.f. Anat., Physiol. u. ivissensch. Med., 1866, S. 151. 

 2 Virchow's Archiv, 1869, Bd. xlvii. S. 357. 

 3 Arch,f, d. yes, Physiol., Bonn, 1870, Bd. iii. S. 578. 



