230 
TROPICAL NATURE 
i 
climate of the equatorial zone are brought about, how it is 
that so high a temperature is maintained during the absence 
of the sun at night, and why so little effect is produced by 
the sun’s varying altitude during its passage from the northern 
to the southern tropic. In this favoured zone the heat is 
never oppressive, as it so often becomes on the borders of the 
tropics ; and the large absolute amount of moisture always 
present in the air is almost as congenial to the health of man 
as it is favourable to the growth and development of vegeta- 
tion . 1 Again, the lowering of the temperature at night is so 
regular and yet so strictly limited in amount, that, although 
never cold enough to be unpleasant, the nights are never so 
oppressively hot as to prevent sleep. During the wettest 
months of the year, it is rare to have many days in succession 
without some hours of sunshine, while even in the driest 
months there are occasional showers to cool and refresh the 
overheated earth. As a result of this condition of the earth 
and atmosphere, there is no check to vegetation, and little if 
any demarcation of the seasons. Plants are all evergreen; 
flowers and fruits, although more abundant at certain seasons, 
are never altogether absent ; while many annual food-plants 
as well as some fruit-trees produce two crops a year. In 
other cases, more than one complete year is required to 
mature the large and massive fruits, so that it is not uncom- 
mon for fruit to be ripe at the same time that the tree is 
covered with flowers in preparation for the succeeding crop. 
This is the case with the Brazil nut tree in the forests of the 
Amazon, and with many other tropical as with a few tem- 
perate fruits. 
Uniformity of the Equatorial Climate in all Parts of the Globe 
The description of the climatal phenomena of the equatorial 
zone here given has been in great part drawn from long 
personal experience in South America and in the Malay 
Archipelago. Over a large portion of these countries the 
same general features prevail, only modified by varying local 
1 Where the inhabitants adapt their mode of life to the peculiarities of 
the climate, as is the case with the Dutch in the Malay Archipelago, they 
enjoy as robust health as in Europe both in the case of persons born in 
Europe and of those who for generations have lived under a vertical sun. 
