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contagious or infectious disease, in practice this is not the case, the 

 permanent materials of which lines are now constructed are readily- 

 disinfected. The line site should be flat, clean weeded and free 

 of all cultivation. There should be not less than 50 feet between 

 each set of lines and at least 200 feet between the lines and the 

 cultivated area. If this allowance of open space is made it will 

 be found, that for say six sets of lines of 20 rooms each, about 

 six acres will be required for the line site. That is none too 

 much for the accommodation of nearly 500 persons but it is a 

 great deal more than is afforded upon the majority of estates 

 where the mistake has been made of planting up close to the 

 lines with the idea that the rubber can be cut back later on, 

 only too often the manager is unable to harden his heart when 

 it has come to cutting out rows of trees well grown and ready 

 for the knife. It must never be forgotten that the lines will, 

 as time goes on, become surrounded by a dense wall of cultivation 

 which in the case of rubber may be 40 feet high and unless that 

 wall is far removed from the lines the labourei's will not get 

 sufficient light, air, and sunshine. Apart from a deficiency of 

 these three essentials to health there is in this country a special 

 danger from cultivation close to cooly lines for it means that 

 the ground adjoining the lines remains damp and in the rainy 

 seasons sodden, conditions eminently suitable for the propagation 

 of hook worm disease. In this connection it should be remembered 

 that the direct rays of the tropical sun have most powerful 

 sterilizing properties. Labourers will acquire no disease from 

 contact with a clean weeded sunbaked line site, a grass grown site 

 may be more picturesque, but refuse rice and debris from the lines 

 Avill be deposited in the grass, flies will breed in it and become 

 a nuisance and a dangerous factor in the spread of diarrhoea, 

 dysentery or other intestinal complaint. There should be plenty 

 of light in the lines, unfortunately both coolies and anopheline 

 mosquitoes prefer darkness and gloom, light will not hurt your 

 coolies but anophelines will and it is therefore well to insist that 

 light shall not be blocked out of the rooms. A further valuable 

 precaution is white- washing of the lines within and without at 

 frequent intervals. It has often been noticed that anophelines 

 are difficult to find in white- washed rooms whilst in adjoining rooms 

 that have not been white-washed they may be found in numbers. 

 In this country anophelines certainly avoid bright daylight and 

 sunlight. It is stated that in the Panama Zone anophelines will 

 remain hungry rather than fly three feet out into the sunlight to 

 bite a person standing in the sun. In the choice of a line site it is 

 important to avoid the proximity of ravines and swamps. Ravines 

 may afford a water supply, they will certainly produce malaria. 

 Swamps are less harmful, and it may be said that ravines and grass 

 grown ditches in which there is a trickle of clear water should be 

 looked upon with greater suspicion than permanent swamp or old 



