84 



recalled from the oil-fields, except one who contracted yellow fever 

 and died ; but as work in the fields was very active, either they would 

 have to be abandoned at enormous financial loss, or the forest had to 

 be rendered safe. The following measures were therefore taken : — 

 (1) no non-immune was allowed to go out for a period of five weeks 

 since the last case was infected there ; (2) clearing the forest for 100 

 feet on each side of the main road running through the oil-fields ; this 

 load was about five miles long ; (3) clearing the forest for a radius of 

 900 feet from the centre of each well or field ; (4) burning the bush, 

 where possible, and draining the area thus exposed ; (5) building 

 screened barracks for the black employees. 



Subsequently the non-immunes were allowed to return, a few at a 

 time, protected by mosquito-proof helmets, gloves and legghigs, and 

 gradually work was resumed at full pressure and no more cases occurred. 

 Active anti-mosquito measures were also taken at La Brea. 



Clare (H. L.). Malaria. — Trinidad and Tobago Council Paper No. 205 

 of 1914, Port-of'Spain, 1915, p. 9. 



The spleen figure of the islands is given at 17-91 per cent, of children 

 of 15 years and under, as agamst 3405 in Ceylon and 34' 1 in Mauritius. 

 A mosquito survey is in progress and large collections of mosquitos 

 are being accumulated ; these will serve as the basis for an organised 

 campaign against malaria. 



Flea destruction as a plague measure.— Indian Med. Gaz., Calcutta, 1, 

 no. 3, March 1915, pp. 104-105. 



Lt.-Col. D. T. Lane, Chief Plague Medical Officer of the Punjab, has 

 stated that numerous experiments at the Malaria Bureau, Lahore, 

 prove beyond doubt, that cresol vapour is extremely poisonous to 

 fleas, though harmless to man and animals. Two ounces of cresol 

 vaporised in a room with closed windows and doors kills the fleas in 

 the room. The cresol used is saponified cresol issued by the Medical 

 Store Depot at 2s. per gallon. There are two methods of using the 

 vapour. (1) Kindle a small cow-dung fire, made of 4 or 5 cow-dung 

 cakes, in a wide iron cup or giijnla till it is smouldering well, but not 

 in flame. Place the cup in the room with the doors and windows 

 closed and pour 2 oz. of cresol on it and let it smoulder till completely 

 burned. This takes about 2 hours. (2) Close the doors and windows 

 of the room, place an angiti containing a fire of any material, provided 

 the fire is not in flame, in any convenient part of the room and put a 

 cup containing 2 oz. of cresol on the angiti and let it vaporise, which 

 it does in about an hour. Either of these methods kills the fleas in a 

 room. Care must be taken that the cresol is vaporised and not 

 ignited. If poured on a flaming fire, cresol ignites and burns with a 

 dense black smoke which is absolutely harmless to fleas. If correctly 

 used, there is no flame, but a greyish vapour which is highly poisonous 

 to fleas, though not offensive or injurious to man or domestic animals. 

 The room should be kept closed until the vapour disappears, which 

 it does in 2 to 3 hours. The work can be tested by placing control 

 fleas in various parts of the room in gauze bags. 



