862 ANIMAL HEAT. 
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 x 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 0, 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 vertebra? caused, in another rabbit, a fall 
in temperature from 38° - 9 to 32°T. 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 - 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, 3 who, working upon rabbits, obtained positive 
results in eleven, negative in twelve cases. They found in one case a 
rise from 39°"31 to -±2° - 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 clue to increased production of heat. Bruck 
and Gunther 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. wissensch. Med., 1866, S. 151. 
2 Virehow's Archiv, 1869, Bd. xlvii. S. 357. 
*Arch.f. d. ges. Physiol., Bonn, 1870, Bd. iii. S. 578. 
