the milk tree. Amid the great number of curious phenomena which have presented themselves to me in the course of my travels, I confess there are few that have so powerfully affected my imagination as the aspect of the cowtree. Whatever relates to milk, whatever regards corn, inspires an interest, which is not merely that of the physical knowledge of things, but is connected with another order of ideas and sentiments. We can scarcely conceive how the human race could exist without farinaceous substances, and without that nourishing juice which the breast of the mother contains, and which is appropriated to the long feebleness of the infant. The amylaceous matter of corn, the object of religious veneration among so many nations, ancient and modern, is diffused in the seeds, and deposited in the roots of vegetables; milk, which serves us as an aliment, appears to us exclusively the produce of animal organization. Such are the impressions we have received in our earliest infancy; such is also the source of that astonishment which seizes us at the aspect of the tree just described. It is not here the solemn shades of forests, the majestic course of rivers, the mountains wrapped in eternal frost, that excite our emotion. A few drops of vegetable juice recal to our minds all the powerfulness and the fecundity of nature. On the barren flank of a rock grows a tree with coriaceous and dry leaves. Its large woody roots can scarcely penetrate into the stone. For several months of the year not a single shower moistens its foliage. Its branches appear dead and dried; but when the trunk is pierced, there flows from it a sweet and nourishing milk. It is at the rising of the sun that this vegetable fountain is most abundant. The blacks and natives are then seen hastening from all quarters, furnished with large bowls to receive the milk, which grows yellow, and thickens at its surface. Some employ their bowls under the tree itself, others carry the juice home to their children. We seem to see the family of a shepherd who distributes the milk of his flock. I have described the sensations which the cow-tree awakens in the mind of the traveller at the first view. In examining the physical properties of animal and vegetable products, science displays them as closely linked together; but it strips them of what is marvellous, and perhaps also of a part of their charms, of what excited our astonishment. Nothing appears isolated; the chemical principles that were believed to be peculiar to animals are found in plants; a common chain links together all organic nature. Long before chemists had recognised small portions of wax in the pollen of flowers, the varnish of leaves, and the whitish dust of our plums and grapes, the inhabitants of the Andes of Quindiu fabricated tapers with the thick layer of wax that covers the trunk of a palm-tree. It is but a few years since we have discovered in Europe caseum, the basis of cheese, in the emulsion of almonds; yet for ages past, in the mountains of the coast of Venezuela, the milk of a tree, and the cheese separated from that vegetable milk, have been considered as a salutary aliment. What is the cause of this singular course in the unfolding of our knowledge? How have the vulgar in one hemisphere recognised what in the other has so long escaped the sagacity of chemists, accustomed to interrogate nature, and seize her in her mysterious progress? It is that a small number of elements and principles differently combined are spread through several families of plants; it is that the genera and species of these natural families are not equally distributed in the torrid, the frigid, and the temperate zones: it is that tribes, excited by want, and deriving almost all their subsistence from the vegetable kingdom, discover nourishing principles, farinaceous and alimentary substances, wherever nature has deposited them, in the sap, the bark, the roots, or the fruits of vegetables. That amylaceous fecula which the seeds of the cereal plants furnish in all its purity, is found united with an acrid, and, sometimes, even poisonous juice, in the roots of the arums, the tacca pinnatifida, and the iatropha manihot. The savage of America, like the savage of the islands in the Pacific Ocean, has learned to dulcify the fecula, by pressing and separating it from its juice. In the milk of plants, and in the milky emulsions, matter extremely nourishing, albumen, caseum, and sugar, are found mixed with caoutchouc, and with deleterious and caustic principles, such as morphin and the hydrocyanic acid. These mixtures vary not only in the different families, but also in the species which belong to the same genus. Sometimes it is the morphin, or narcotic principle, that characterizes the vegetable milk as in some papaverous plants; sometimes it is caoutchouc, as in the hevea, and the castilloa; sometimes albumen and caseum, as in the cow-tree. Ceroxylon andicola, which we have described in our Plantes Equinoctionales, vol. i. p. 9. pl. i. and ii. Proust in the Journ. de Physique, vol. liv. p. 430. Boullay and Vogel, in the Annales de Chimie et de Physique, vol. vi. p. 403. Opium contains morphin, caoutchouc, &c. Humboldt, vol. iv.