5i6 Veterinary Medicine. 



of these Indians from tuberculosis is 50 per cent, of the total 

 mortality.' Dr. Washington Matthews, who spent twenty-one 

 years among the Indians, gives their food as the main cause of 

 the disease, and states that when the supply of fresh meat is 

 Uberal the death rate from tuberculosis is highest (Census of 

 1880). 



If we now contrast this fearful mortality with the immunity of 

 the Indians of Hudson Bay, Great Slave I^ake, Alaska, and the 

 North generally, we have a most suggestive picture. It may be 

 conceded that the extreme Northern Indians, being beyond the 

 cereal region, have a slight measure of protection in their meat 

 diet ; but the recent spread of tuberculosis like a plague among' 

 the inhabitants of Barrow Straits, when introduced by the frozen- 

 in whalers and the relief party, is sufficient disproof of any claim of 

 special insusceptibiUty. There can be no doubt that in this, as 

 in other virulent diseases, the rule holds that the long absence of 

 the infection secures the preservation of the susceptible lines of 

 blood, so that when the contagion does come it finds a more in- 

 viting field than in countries in which the more susceptible strains 

 have been killed off and the comparatively immune have survived. 

 Toward the Arctic circle the Indian must crowd into closer quar- 

 ters in winter than his brother further south ; but, in spite of all, 

 the beef-eating Indian is being rapidly exterminated by tubercu- 

 losis, to which his brother of the north is a comparative stranger. 



Exceptions : their Explanation. This statement would be in- 

 complete without a notice of exceptions to the rule. The Cape 

 Town branch of the British Medical Association reports ' ' that 

 tuberculosis is rapidly increasing there in the human population, 

 while tubercle in cattle is almost non-existent." This finds an. 

 abundant explanation in the different conditions of life. The 

 men live in-doors and concentrate the infection, whereas the cattle 

 enjoy an out-door life and escape. In a latitude of 30° south, 

 where frost is rare, and with a dry climate (12 to 30 inches 

 of rain per annum) , the colonists find no occasion for housing their 

 cattle, so that the conditions for the prevention of tuberculosis are 

 ideal. It may be added that cattle are far less numerous in Cape 

 Colony than they formerly were. The destruction first by lung 

 plague and later by rinderpest has made the cattle industry ex- 



•Medical Record, August 13, 1883. 



