HENSEL, H. 
DR. HENSEL: Eight as yet. 
COL. QUASHNOCK: Did you suture the nerves after cutting 
them? 
DR. HENSEL: No, because it was only a thin bundle 0.5 mm in 
diameter. We only cut this small part of the nerve, whereas the 
whole remaining part was undamaged. 
DR. LIM: And you did not observe any warm receptors in all 
these subjects? 
DR. HENSEL: No, we always saw an increase in frequency 
during cooling and a decrease during warming. But we have not 
studied the C fibers as yet. I am quite sure that warm receptors 
could be found in the C group. 
DR. HEMINGWAY: Have you any idea what end organs are 
involved? 
DR. HENSEL: I can say only that there are some areas in 
human skin which contain only so-called free nerve endings. From 
these areas, any kind of sensation can be elicited. This holds true 
also for the tip of the tongue in the cat. A thorough histological 
stucty of this area has been made by Dr. Kantner in Heidelberg 
(1957). He found only a network of free nerve endings in the tip of 
the tongue — except the taste buds, of course. As you can see in 
Figure 1, there are quite specific pressure and cold impulses, in 
spite of the absence of any encapsulated specialized nerve endings 
such as Krause's and Meissner's end organs. 
DR. IRVING: I notice, sir, that the records from many of your 
cold stimulations cease at certain cold temperatures. Ami correct 
about this? 
DR. HENSEL: Well, the lowesttemperature for maximum firing 
that we have found so far in C fibers was about 16 C. Some C fibers 
were still firing at a temperature of 5 C, but at a very low rate. 
DR. FREEMAN: How much vibration in the thermode do you 
get as a result of passage of water through it? 
62 
