182 
SECOND BOOK. 
4. If we wish to avoid a district where much rain 
falls, we must consider the direction of the winds. 
The trade-winds bring with them a large quantity 
of moisture, which they gathered up as they swept 
over the ocean. When they become chilled by the 
highlands they can no longer hold their moisture, 
which therefore falls in plentiful showers. 
5. From this cause the north-east part of Jamaica — 
the part facing the rain-bearing winds of winter — 
has a large rainfall in November and December. 
On the other hand, in the south there are summer 
rains in August and September. 
6. We are well aware that air which is not kept 
moving becomes unhealthy, and that houses are not 
likely to be free from dampness if the air cannot 
pass thoroughly into them. Therefore, wherever 
our house may stand, it should not be surrounded 
closely by bush, for this would prevent the air from 
blowing freely round about it. It is, however, a 
good thing to have a few tall trees to give shade, 
though these should not overhang the house. 
7. Where plants and trees grow thickly over 
large areas they make a great difference in the 
dampness of a climate. They screen the soil from 
the rays of the sun, so that the air above it becomes 
cooled, and consequently sends down rain. They 
also suck up much moisture from the soil, and give 
it off to the air through their leaves. 
a Enough has been said to show that there are 
