134 



Mr. GiLMAN, who had also tried oiling on Bukit Jelutong Estate, 

 said that, when he started, the death-rate on his estate in AvTgust, 

 1915, was 88 per mille, at the end of that year it came down to 69. 

 In 1916 the death-rate was 3 per mille. This year they had not had 

 a death yet. He had 159 coolies and only had one death, from 

 pneumonia, during the year. 



Mr. HusoN asked for more information about the method of 

 spraying. 



IMr. Habrison explained that he employed four coolies in each 

 division with four sprayers, with a definite programme mapped out 

 for each. They used crude oil in 65-gallon drums which were 

 used for liquid fuel. One ordinary kerosene oil tin filled a spraying 

 machine. Every scrap of water in the area was oiled, in fact they 

 even went across the road into the surrounding kampongs and oiled 

 the wells tliere. (Laughter.) 



Mr. Jabvis thought the experience of Midlands, Avhere half a 

 mile of oiling was sufl3cient, did not agree with the statement that in 

 Panama anophelines would fly a mile against wind, and asked 

 Dr. Lucy what he considered was the limit of a mosquito's operations. 



Dr. Lucy replied that as to mosquitoes travelling for over half a 

 mile, he could not say definitely, but many estates which had tried 

 oiling found a radius of half a mile gave good results. It was 

 not possible to lay down a hard and fast rule as to what distance 

 anopheles travelled. In Panama experiments with painted anopheles 

 showed "that some travelled as fai* as 6,000 feet. 



Mr. Lawford asked what was the safe margin around which 

 water should be oiled P 



Dr. Lucy said a great deal of enquiry was necessary before a 

 hard-and-fast rule could be laid down. Certainly half a mile was 

 the absolute minimum, and the further they went the better. Bach 

 case must be taken on its merits. As to the habits of mosquitoes, 

 that was a question they knew very little about, though the 

 anophelines prefeired clear running water, and were seldom found in 

 dirty water. It was a question which required a good deal of 

 research, and lie hoped a man would be appointed to enquire into 

 that in the future. He had seen anophelines in the overflow from 

 factories, but they didn't like it. 



Mr. Harbison said that he would like to know what Dr. Lucy 

 thought about mosquito-proof lines and the leaving of ravines in 

 blukar for the prevention of malaria. 



Dr. Lucy replied that as regards mosquito-proof lines he knew 

 of two or three estates which had attempted it. Many years ago 

 mosquito-proof hospitals were started in Negri Sembilan. There 

 was not the slightest doubt that it did some good, but there was 

 another side to the question. There was immense difficulty in 



