APPRECIATION OF TEMPERATURE. 135 



seemed to be greater, although it was really less, when they were placed 

 upon more sensitive parts. 



It has been supposed, that some of the recorded instances of great 

 resistance to heat have been caused by unusual thickness, and com- 

 pactness of cuticle, together with a certain degree of insensibility of 

 the skin. The latter may be an important element in the explanation ; 

 but some of the feats, executed by persons of the character alluded to, 

 could hardly have been influenced by the former, as the resistance 

 seemed almost equally great in the delicately organized mucous mem- 

 branes. A Madame Girandelli, who was exhibited in Great Britain 

 many years ago, was in the habit of drawing a box with a dozen 

 lighted candles along her arm, putting her naked foot upon melted 

 lead, and of dropping melted sealing-wax upon her tongue, and im- 

 pressing it with a seal, without appearing to experience uneasiness; and 

 several years ago (1832), a man of the name of Chabert excited in 

 this country the surprise which followed his exhibitions in London a 

 year or two previously, and gave him the appellation of the " Fire 

 King." In addition to the experiments performed by Madame Giran- 

 delli, Chabert swallowed forty grains of phosphorus ; washed his fingers 

 in melted lead ; and drank boiling Florence oil with perfect impunity. 

 For the phosphorus he professed to take an antidote, and doubtless did 

 so. It is probable, also, that agents were used by him to deaden the 

 painful impressions ordinarily produced by hot bodies applied to the 

 surface. A solution of borax or alum spread upon the skin is said to 

 exert a powerful effect of the kind; but, in addition to the use of such 

 agents, there must be a degree of insensibility of the corpus papillare; 

 otherwise it is difficult to understand why those hot substances did not 

 painfully inflame the surface. We see, daily, striking differences in 

 individuals in the degree of sensibility of the mucous membrane of the 

 mouth and gullet, and are frequently surprised at the facility with which 

 certain persons swallow fluids of a temperature that would excite the 

 most painful sensations in others. In this, habit has unquestionably 

 much to do. 



In the mucous membranes, tact is effected in the same way as in the 

 skin. The layers, of which it is constituted, participate in like man- 

 ner; but the sense is more exercised at the extremities of the mem- 

 brane than internally. The food, received into the mouth, is felt 

 there ; but after it has passed into the gullet it excites hardly any tac- 

 tile impression; and it is not until it has reached the lower part of the 

 membrane, in the shape of excrement, that its presence is again indi- 

 cated by this sense. 



Pathologically, we have some striking instances of this difference in 

 different parts of the mucous membrane. If an irritation exists within 

 the intestinal canal, the only indication we may have of it is itching of 

 the nose, or at one extremity of the membrane. In like manner, a cal- 

 culus in the bladder is indicated by itching of the glans penis; and a 

 similar exemplification is offered during the passage of a gall-stone 

 through the ductus communis choledochus. On its first entrance, the 

 p^i experienced is of the most violent character; this, after a time 

 strosides, as soon, indeed, as the calculus has got fairly into the canal. 



