POINTS IN MANAGEMENT. 95 



and elements in contact. At a low atmospheric tem- 

 perature, the superficial parts of the body part with their 

 heat more rapidly than it can be generated and diffused 

 under the action of combustion of a given quantity of 

 carbonaceous matter taken in the food. The effect of cold, 

 when below a certain degree, is to contract the parts, 

 contract the blood-vessels, and force back the blood ; 

 consequently, to impede the process of formation, or 

 reconstruction, which is dependent for its reahsation on 

 the blood, and in a certain temperature being maintained 

 in aU the parts. A larger amount of carbonaceous food, 

 within limits, being supplied, the equihbrium of evolution 

 of heat and its generation, is more nearly maintained. 



Shelter, producing a warmer surrounding atmosphere, 

 and non-conductors used as covering, diminish the neces- 

 sity for an increased quantity of heat-giving food, and are, 

 in effect, equivalent to a certain amount of food. The 

 absence of shelter and external warmth cannot, however, 

 be wholly compensated by food. An unusual degree 

 of cold produces an effect, inevitably. The skin, and 

 parts adjacent, will always be affected, as wiU also the 

 natural covering — hair, or wool, of animals. The con- 

 traction of the hide and inner skin — from which the wool 

 springs and draws the means of growth — restricts the 

 passage into the wool of the elements of its growth, and 

 diminishes the supply of yolk — which is its natural protec- 

 tion and softener — and it becomes wanting in texture and 

 elasticity. In hke manner, the wool suffers from the 

 effect of wet. The yolk is not of the wool, but is" pro- 

 vided as its protection. Its composition is oleaginous and 

 alkaline ; mainly, animal grease and compounds of pot- 

 ash ; forming, in fact, a true soap, which is washed away 

 by rain, leaving the wool comparatively dry and harsh. 



The action of external heat greater than the normal 



