322 TEMPERATURE TOPOGRAPHY. 



Skin [J. Lkwy). 



II iddle of the sole of the foot 32 *26^ 



ir ten Jo Achillis, . 33*85 



Anterior surface of leg, . 33*05 



Middle of calf, . . 33 85 



Bend of knee, . . . 35*00 



Middle of upper arm, . . 35*40 



Inguinal fold, . . 35-80 



Near cardiac impulse, . . 34 "40 



Face, 3100 



Nose and tip of ear, . . 22 "24 



In the closed axilla, 36 49 (mean, of 505 individuals) ; 36 '5 to 37*25 ( Wunderlich) ; 36*89 C. 

 {Licbermcister). The skin over muscles is warmer than that over bone (Kunkel). 



The temperature of the skin of the head is higher in the forehead and parietal region than in 

 the occipital region ; the skin on the left side of the head is warmer than on the right. 

 Dyspnoea increases the temperature of the skin. 



Method. Liebermeister determines the temperature of free cutaneous surfaces thus : The 

 hulh of the thermometer is heated slightly above the temperature expected ; after the mercury 

 lie-gins to fall, the bulb is placed on the skin, and if the bulb has the same temperature as the 

 .skin, the mercury remains stationary. This experiment must be repeated several times. 



2. Cavities. 



Mouth under the tongue, . 37*19 C.I Vagina, 38*30 C. 



Rectum, . . . .38*01 I Urine, 37*03 



Uterine cavity somewhat warmer ; cervical canal of the uterus somewhat cooler. 

 The temperature falls in the stomach during digestion ( 166, 1). Cold injec- 

 tions (11 C.) into the rectum rapidly lower the temperature in the stomach 1 C. 

 ( Winternitz). 



3. The temperature of the blood is, as a mean, 39 C. The venous blood in 

 internal viscera is warmer than the arterial, but it is cooler in peripheral parts : 



The lower temperature of the blood in the left heart may be explained by the blood becoming 

 cooled in its passage through the lungs during respiration. According to Heidenhain and 

 Kbrner, the right heart is slightly warmer because it lies in relation with the warm liver, whilst 

 the left heart is surrounded by the lung, which contains air. This observation is disputed by 

 others, who say that the left heart is slightly warmer because the combustion-processes are 

 more active in arterial blood, and heat is evolved during the formation of oxyhemoglobin. The 

 blood in the veins is usually cooler than in the corresponding arteries, owing to the superficial 

 position of the former, whereby they give off heat during their long course ; thus the blood of the 

 jugular vein is to 2 s C. lower than the blood in the carotid ; the crural vein to 1 cooler than 

 in the crural artery. Superficial veins, more especially those of the skin, give off much heat, 

 and their blood is, therefore, somewhat cooler. The warmest blood is that of the hepatic vein, 

 39*7 C, partly owing to the great chemical changes which occur within the liver, from its 

 .secretory activity ( 210, a), and partly to its protected situation. 



4. The individual tissues are warmer: (1) the greater the transformation of 

 kinetic energy into heat, i.e., the greater the tissue-metabolism j (2) the more blood 

 they contain ; (3) and the more protected their situation. According to Heidenhain 

 and Kbrner, the cerebrum is the warmest organ in the body. 



Subcutaneous tissue (sheep), 37*35 C. i Rectum 40*67 C. 



Kr *in, . . . 40*25 Right heart, . . . 41*60 



] AV ^, ..... 41*25 Left heart, . . . 40*90 



Lungs, . . . . 41*40 | (Bcrger.) 



Hec'juerel and Brechet found the temperature of the human subcutaneous tissue to be 2*1 C. 

 lower than that of the neighbouring muscles. The horny tissues do not produce heat, and 

 their low temperature is due to the conduction of heat from the parts on which they grow. The 

 temperature of the cornea partly depends on that of the iris, and the more contracted the pupil 

 is, the more heat it receives from the blood-vessels of the iris. 



210. CONDITIONS AFFECTING THE TEMPERATURE OF ORGANS. 



The temperature of the individual organs is by no means constant ; it is influenced 

 by many conditions ; amongst these are the following : 



(1) The more heat produced independently within a part, the higher is its tempera- 

 ture As the amount of heat produced within apart depends upon its metabolism, 



