In South America is the remarkable fall of Tequendama, on the river Bogota, which, at this point, is only one hundred and forty feet wide, and is divided into numerous narrow and deep channels which finally unite in two of nearly the same width, and make a perpendicular plunge of six hundred and fifty feet to the plain below. "The cataract," says Humboldt, "forms an assemblage of everything that is sublimely picturesque in beautiful scenery. It is not one of the highest falls, but there scarcely exists a cataract which, from so lofty a height, precipitates so voluminous a mass of water. The body, when it first parts from its bed, forms a broad arch of glassy appearance; a little lower down it assumes a fleecy form, and ultimately, in its progress, it shoots forth in millions of smaller masses, which chase each other like sky-rockets. The attending noises are quite astounding, and dense clouds of vapor soar upward, presenting beautiful rainbows in their ascent. What gives a remarkable appearance to the scene is the great difference in the vegetation surrounding different parts of it." At the summit the traveler "finds himself surrounded, not only with begonias and the yellow bark tree (Sandal), but with oaks, elms, and other plants, the growth of which recall to mind the vegetation of Europe, when suddenly he discovers, as from a terrace and at his feet, a country producing the palm, the banana, and the sugar-cane. The cause of the difference is not ascertained, the difference of altitude--one hundred and seventy-five metres--not being sufficient to exert much influence on the atmosphere." [Illustration: NEVADA FALLS] Another and grander South American fall, of comparatively recent discovery, is the Kaiteeur, so called, in the river Potaro, a large affluent of the Essequibo, the largest river in British Guiana. The volume of water is greater than that in the Bogota, and falls in a single column of dazzling whiteness seven hundred and forty feet into a vast basin below. The ascending cloud of spray, the solemn monotone of the descending flood, the extreme wildness of the primitive forest, and the luxuriant and abundant growth of tropical vines and shrubs, and their gorgeous colors, make the scene impressive. [Illustration: LOWER FALLS OF THE YELLOWSTONE]