56 INFLAMMATION. 



dull; though heat occasionally must exist, as is evident from 

 its penetrating the thickness of the hoof : which it does, and 

 to a degree that renders the part actually hot under the 

 hand. The expired air, in cases of inflamed air-passages, is 

 so charged with heat as to convey really a burning sensation. 

 There cannot, therefore, be entertained a doubt respecting 

 the increase of temperature in external parts. But it is 

 different in regard to internal organs : they are not subject 

 to those fluctuations of temperature to which the external 

 are exposed ; moreover, every internal part is already of the 

 natural heat of a living body, to which any vital action can 

 add but very little. Mr. Hunter excited a high degree of 

 inflammation within the rectum and vagina of an animal, 

 without being able to augment the temperature of those 

 cavities above a degree of the thermometer : in fact, he 

 concluded, that " the heat could hardly be said to be 

 increased. ^^ We may, therefore, lay down two axioms 

 concerning heat in inflammation — that the temperature 

 may be augmented, in any external part, as high as the 

 natural standard of the body, or be raised to 100° Fahr. ; but 

 with internal parts already of this temperature, inflamma- 

 tion, though attended with the sensation of heat, is not found 

 to become in reality augmented (or but very little) beyond 

 that point. The truth being, that heat is generated much 

 more rapidly than in health, and consequently acts on the 

 feelings of the patient, as well as on the perception of 

 another person ; although the actual temperature, from the 

 heat being carried off' as fast as produced, undergoes but 

 very trifling augmentation. 



Pain, though equally present as a symptom of inflamma- 

 tion, and probably equally variable, yet is one concerning 

 which we can learn only from careful observation. Ani- 

 mals, it is true, feelingly and impressively exhibit their 

 sufferings; solicit our aid by signs too plain to admit of 

 being misunderstood; for all this, however, though they 

 may make us sensible of the intensity of their pain, they 

 often leave us much in the dark respecting the nature of 

 the agony they endure. In the generality of cases we are 



