TEMPERATURE-TOPOGRAPHY. 387 



aorta is from 0.1 to 0.6 lower than that of muscle at rest. In the 

 second place, the glands generate heat, especially during activity, par- 

 ticularly the liver, the salivary glands, the glands of the stomach and 

 the intestines. 



Berger took the temperature of different tissues in the sheep and obtained 

 the following results : 



Subcutaneous connective tissue 37-35 C. 



Brain 40.25 C. 



Liver 4i.25C. 



Lungs 4 i . 4 o C. 



Rectum 40.67 C. 



The right heart 41.40 C. 



The left heart 40.90 C. 



In man, Becquerel and Brechet found the temperature of the subcutaneous 

 connective tissue 2 . i C. lower than that of the adjacent muscles. The temperature 

 of the cornea and of the aqueous humor depends in part upon the state of the 

 iris. The smaller the pupil, the more heat must they receive from the vessels of 

 the iris. 



INFLUENCES AFFECTING THE TEMPERATURE OF INDIVIDUAL 



ORGANS. 



The temperature of the individual organs is by no means constant, 

 but there are numerous influences that at times cause it to rise and 

 at other times cause it to fall. 



i. The more heat a portion of the body generates independently 

 within itself, the higher will be its temperature. As the production of 

 heat depends upon the metabolic changes in the organs, it follows that 

 with the activity of the latter the degree of heat-production must keep 

 pace. 



(a) The glands during secretion produce much heat, which they 

 impart either to their secretion or to the outflowing venous blood. 



C. Ludwig found the temperature of the escaping saliva on irritation of the 

 tympanico-lingual nerve 1.5 C. higher than that of the blood passing through 

 the glandular artery to the secreting organ. The temperature of the venous blood 

 in the secreting kidney is higher than that of the arterial blood. The secreting 

 liver in particular produces a large amount of heat. Claude Bernard studied the 

 temperature of the blood in the portal vein and of the blood in the hepatic veins 

 during hunger, at the beginning of digestion and at the height of digestion, and 

 found 



Temperature of portal vein 37 .8 C. ) After fasting for four days. Blood ot 



hepatic veins. . . . 38.4 C. j right heart during fasting 38.8 C. 



Temperature of portal vein . . . . 39.9 C. | A h beginning of digestion, 

 hepatic veins 39-5 C. i 



Temperature of portal vein 39.7 C. ) At the height of digestion. Blood of 



hepatic veins. ... .41.3 C. I right heart during digestion 39.2 C. 



In dogs feeding or chemical or mechanical irritation of the gastric mucous 

 membrane, and even the holding of food before the animal, brought about elevation 

 of temperature in the stomach and the intestines. 



(6) The muscles produce heat in their contraction. J. Davy found 

 the temperature of active muscle higher by 0.7. Becquerel observed in 

 1835, by means of the thermo-galvanometer, an increase of i C. in the 

 temperature in the interior of a contracting muscle in man after five 

 minutes. 



