112 WONDERS OF THE TROPICAL FORESTS. 
to tlie port, ready to clotite the Australian gold-digger or 
the labourer on the hanks of the Ganges. 
When we consider tbe luxuriance of vegetation in the 
tropical zone, it is not to be woudered at that so many 
plants of tliose cliniea abound with juices of a variety and 
richness unknown to those of the temperate latitudes. 
Tlie resins and gums which onr indigenous trees produce, 
eitlier in smaller quantities or fit only for common uses, 
are there endowed with higher virtues, and ennobled, as it 
were, by the rays of a more powerful sun. Sometimes 
qAOtJTCHOUC TREES— ISPIASS mClSIKO THBM, 
they exude spontaneously through the rind and harden 
in the atmosphere: more frequently a slight incision ia 
required to make tlie sap gush forth, but in everr case 
they require but trifling labour for tbeir collection. 
Many of them have medicinal qualities, others are 
esteemed for their aromatic odonr, but none i*ank3 
higher in a commercial and techtiical point of view 
than caoutchouc or indiaruhber, which was first brought 
from South America to Europe as a great curiosity at 
the beginning of the last century, and is now absolutely 
