INTRODUCTION. 11 



from it. The clinical thermometer (self registering) is 

 the instrument used, and proves a most valuable aid to 

 the veterinary inspector of contagious disorders. The 

 vagina, mouth, and preferably the rectum, are the seat of 

 insertion. The instrument requires to be '^ set " to near 

 the expected reading, as by warmth from the hand, to be 

 introduced a short way and then moved farther in, and to 

 be rested against the walls of the cavity for about three 

 minutes. These precautions are mentioned, as neglect of 

 them may lead to imperfect observation. Ordinary 

 physiological influences as exercise, digestion, &c., give 

 rise to slight variations of internal temperature, but a rise 

 of 2° or 3° is sufficient to lead us to suspect some febrile 

 disturbance, and it has been found that a rise of the 

 internal temperature is the earliest perceptible indication 

 of various eruptive fevers. It therefore is a valuable 

 indication of the advisability of separation when it occurs 

 in animals which have run risk of contagion. A marked 

 fall in temperature below the normal occurs in most cases 

 shortly before death, and a low temperature is observable 

 in typhoid fever and other diseases of a low or asthenic 

 type. When this instrument is not available we must 

 resort to the usual methods of investigation of the surface 

 temperature. Coldness or the reverse of the extremities, 

 of the mouth, of the expired air, must be estimated by our 

 sense of touch, while care is taken to note any variations of 

 these points, either at different times or at one and the same 

 time among similar members. Any tendency to coldness or 

 unequal temperature of these parts must be viewed with 

 suspicion, as indicating deficiency or perversion of the blood 

 supply whereby heat is diffused throughout the body. 

 Excessive warmth indicates febrile conditions. A fall in 

 temperature of the surface is generally a precursor of 

 death, so we often read of "deathly coldness of the 

 extremities.^' The conditions of the skin also require 

 attention, it is the principal regulator of internal tempera- 

 ture, and the effects of its disorder are well seen in the 

 rise of the mercury in fever cases. Its supply of blood 

 and its nervous organisation are very marked, so it is 



