In the regions between ten degrees on either side of the equator lies the major part of this primeval forest. Forest and rivers alike depend on the rain. The moist trade winds, which blow westward from the Atlantic, meet the cold blasts from the lofty, snow-capped Andes, and precipitation follows. The forests protect the rivers by preventing evaporation, and the rivers nurse the trees by increasing the moisture in soil and air. Thus this region, which has the greatest rainfall in the world, has produced the mightiest river and the largest stretch of forest on the globe. Like a huge wall rise the tall trees on every hand. A photograph of a thousand feet of the bank at one place would answer for the same amount of bank at any other place, except that the palms might predominate in some places more than at others. There are no solitary tree trunks; neither are there groups of trees of the same species. It would scarcely be possible to find a half-dozen trees of the same kind to the acre. Penetrate this forest and you have the feeling of having entered a maze or a web. There are plants and trunks but no leaves near the ground. It is the vines that cause one to feel that he has been entrapped. Vines are here, there and everywhere. The great tree trunks are wreathed with them, and the branches above are woven together with them into a labyrinth of leaves and stems. They are not little puny stems, such as may be found in our northern woods, but many of them are giants with woody fibre, almost like that of the tree trunks themselves. They ascend one tree and stretch across a half a dozen others; and then may drop down to the ground again. They are twisted, knotted and looped into almost every conceivable shape. Some have smooth stems and others are covered with spines; some are round or square, and others are gathered together into bundles.