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and a large store of grain for them, and though the place 

 used to swarm with them, until in one year about 12 years 

 ago we killed in various ways about 160, without any poison, 

 and in spite of some very unsuccessful professional 

 assistance. It occurred to me that by offering them 

 the same enticement that one offers as a bait to moths, 

 rum and sugar, their brains would be clouded, they would 

 become much less cunning in detecting a trap, and by this 

 device most of the 160 were taken, including the largest, 

 17fin. long. I must apologise for this digression, but thought 

 that the idea might be of use to some sufferers in the present 

 rat scare. One of the latest methods of destroying rats and 

 rat-fleas, without which as carriers to the human subject the 

 rats are comparatively harmless, but which are, I believe, 

 very rare in this country is by generating prussic acid 

 gas in the room where they are a method apparently 

 very successful in experiment, but impossible to apply, I 

 should think, in most cases, and most dangerous. Whilst 

 I am on this subject I will mention one other so-called new 

 method of destroying mosquito larvae in water with chloride 

 of lime. This method I have used for many years for clearing 

 a rainwater tank of these and other small organisms. It 

 is most effectual, very easily applied, leaves the water 

 wholesome and pure, and kills all animal life in it. Rice 

 fields have been found to be remarkably free from malaria, a 

 fact which may be of much use in the campaign against it. 

 A permanent committee has been appointed in India to deal 

 with anti-malarial measures. One of the latest discoveries 

 in connection with this class of diseases is that Pellagra, 

 chiefly an Italian disease, is due to a protozoon conveyed by 

 the bite of a sandfly (Simulium sp.). The protozoa! parasite 

 itself has not, as in the case of yellow fever, been yet actually 

 seen, and may be too small for our microscopes. A new 

 trypanosome, causing a special disease in human beings, has 

 been discovered in Brazil, and its life history, which presents 

 some unusual features, carefully worked out. All these 

 discoveries, especially, perhaps, the histories of malaria and 



