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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 sa / 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 labourers 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 &, clean weeded sunbaked line site, a grass grown site 
may be more picturesque, but refuse rice and debris from the lines 
will 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 anopheliues 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 
