530 Veterinary Medicine. 



ing the legs with ice cold water when the animal has just re- 

 turned to the stable heated and perspiring. If then left undried 

 and unbandaged in a cold draught these conditions are still 

 farther aggravated. This was formerly attributed to the sup- 

 pression of perspiration, but it occurs in an animal which has 

 just perspired freely and is now in no special need of further 

 elimination through the skin. It appears to be due rather to 

 the action of the cold on the nerve endings, the susceptibility of 

 which has been enhanced by the free secretion and general relax- 

 ation. 



But potent as cold is in precipitating or aggravating an attack, 

 it cannot be looked on as the sale or essential cause of rheuma- 

 tism. The great majority exposed to the cold escape. The 

 animal which has stood in the stall, or shed, is less likely 

 to be attacked than the one at work in which the heat pro- 

 duction has been more active. In leed an immunity has been 

 claimed for the Artie regions, provided the subject is not exerted 

 so as to cause perspiration. One miglit readily conclude that this 

 apparent immunity, depended on the absence of an essential 

 germ, as is also claimed for catarrhs, yet Nansen after his pro- 

 longed bath in the frigid waters seems to have had an attack of 

 rheumatism. Cold appears to be one of the most potent accessory 

 causes, but evidently not in itself the essential cause. 



Cold undoubtedly affects profoundly the metabolism of the 

 body and especially when the vital powers have been reduced by 

 severe exertion, fatigue and perspiration. Tlie same applies to 

 many other affections especially such as are associated with an 

 infecting element, which takes occasion of the debility caused by 

 the cold to establish itself in the tissues. 



Lactic acid and other metabolic products. Prout long ago 

 claimed that rheumatism was caused by an excess of lactic acid 

 in the system, and tiiis was supported by the fact that an e.Kclu- 

 sive diet of buttermilk given in diabetes, is likely to produce 

 acute articular rheumatism. Again the production of rhachitis in 

 the young can be traced in certain cases to excess of this acid. 

 The strongly acid odor of the sweat in certain rheumatic attacks 

 is thought.to support this theory. The excess of lactic acid is 

 variously explained by the overwork of the muscles of which it 

 is the normal product, and by the imperfect oxidation of the 



