The Cow Tree. — Here are no splendid shadow-trees (says Humboldt in his Travels), no majestic streams, and no eternally snow-covered mountains, which mightily move us. A few drops of vegetable sap remind us of the almightiness and fruitfulness of nature. On the sterile declivity of a rock there grows a tree whose leaves are dry and tough, whose thick, woody roots can hardly penetrate the stony soil; for several months in the year, no refreshing rain moistures its foliage, the branches seem dead and shrivelled: but make an incision in the stem, and a sweet nourishing milk flows from it. At sunrise this vegetable spring is the richest; then the negroes and the natives come from all sides, provided with large vessels to collect the milk, which turns yellow, and thickens on the surface. Some empty their vessels, at once, under the tree, others take the milk to their children. One seems to see the establishment of a shepherd who distributes the milk of his herds.