COLD AND WARMTH SENSATIONS. 949 



between glass phials filled with oil and warmed, or cooled in water, but 

 of course applied dry. But the regional degree of development of 

 thermal sensitivity in the skin may be more truly estimated in another 

 way. If media with a contact surface of about 100 sq. mm., and at 

 temperatures more than 15° C. to 17° C. below or above that of the area of 

 skin to be tested, be employed for an appropriate time, they excite from 

 the skin maximal sensations 1 respectively of cold or warmth, which 

 cannot be increased by further increase of the physical intensity of the 

 stimulus. The maximal sensation thus evoked varies much in intensity 

 in different regions. 



Twelve grades can be readily distinguished in " cold " sensation, and eight 

 grades in "warmth" sensation. 2 The following scale was obtained by using 

 brass cylinders of 1 cm. diameter. 3 The scale commences with the places 

 yielding lowest maximal intensity of sensation : — 



Cold Sensations. 



1. Tips of fingers and toes, malleoli, ankle. 



2. Other parts of digits, tip of nose, olecranon. 



3. Glabella, chin, palm, gums. 



4. Occiput, patella, wrist. 



5. Clavicle, neck, forehead, tongue. 



6. Buttock, upper eyelid. 



7. Lower eyelid, popliteal space, sole, cheek. 



8. Inner aspect of thigh, arm above elbow. 



9. The intercostal spaces along the region of the axillary line. 



10. Mammary areola. 



11. Nipple, flank. 



12. Certain areas of the loins and abdomen. 



The period of application of the brass surface for obtaining " warmth 

 maxima " has to be more prolonged than that required for testing " cold 

 maxima," 1*5 seconds instead of "5 second. 



Warmth Sensations. 



0. Lower gum, mucosa of cheek at lower second molar, cornea. 



1. Tips of fingers and toes, cavity of mouth, conjunctiva, patella. 



2. Remaining surface of digits, middle of forehead, olecranon. 



3. Glabella, chin, clavicle. 



4. Palm, buttock, popliteal space. 



5. Neck. 



6. Back. 



7. Lower eyelid, cheek. 



8. Nipple, loin. 



The observations, to a certain extent, bear out what might have been 

 supposed, namely, that those portions of the body surface habitually 

 protected by clothes would possess higher sensitivity to cold than parts 

 habitually naked. The clothed parts of the body are, however, as will 

 be seen later from other observations, less embued with power to 

 discriminate between small degrees of difference of cold than are many 

 other and unclothed parts. 



When fluids quite cold, e.g. at 2° C, or quite hot, e.g. at 50° C, are 

 swallowed, sensations of cold or of warmth are felt in the mouth and at the 



1 Goldscheider, Arch./. Psychiat., Berlin, 1887, Bd. xviii. S. 659. 



" Goldscheider, ibid. 



3 The method is called by Goldscheider a method for testing the "absolute sensitivity." 



