CLIMATE 997 



becomes extraordinarily active both in tropical and sub- 

 tropical regions. It is inconceivable the myriads of insects 

 and scores of varieties which come from the ground after 

 the first rain ; the extraordinary thing is they come out in 

 the adult form, active, full of life and energy, just as if they 

 had been waiting under cover for months for the rain to 

 appear. Among the insects which put in an appearance is 

 the intermediate host of Horse Sickness ; it is this insect and 

 not the rain which produces the disease. 



In Indian anthrax the rain mainly acts by distributing 

 the spores over the soil, while the high temperature which 

 exists at this time of the year facilitates the growth of the 

 organism. 



Diseases like rheumatism are without doubt more frequent 

 during wet or damp weather, but rheumatic affections of 

 animals are rare. 



If we regard climate as made up of heat, cold, rain, wind, 

 and altitude, an excess of any of these may kill or greatly 

 influence the body, but there is nothing in them specifically 

 unhealthy, so that unhealthy climates, so called, are due to 

 other causes, some of which we have outlined above. 



If now we come to consider Acclimatization we are met 

 by still more difficulties ; very little exact knowledge exists 

 as to the changes occurring in the body, which render an 

 animal capable of living in a totally different climate to 

 the one in which it has been born and brought up. 



In matters of altitude there is no doubt the system 

 rapidly adapts itself to the reduction in pressure ; but 

 altitude in the case of the herbivora means a change in forage 

 plants, and what may be attributed to reduced pressure is 

 probably nothing more than the stomach and intestinal 

 canal adjusting itself to the change in food. The danger 

 incurred of passing from highlands to lowlands is mainly 

 dietary, while in tropical and subtropical countries there is 

 in addition the question of passing to an area of increased 

 activity in insect life, for this latter is to an extent controlled 

 by moderate altitude, and practically completely held in 

 check by considerable altitude. 



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