In the foremost rank of those who have possessed the twofold qualification of scientific knowledge and descriptive power, we must place the illustrious Humboldt. His works are a rich storehouse from which later writers have freely borrowed the materials of their essays. In reference to the phrases " Virgin Forest," "Primeval Forest," he has some judicious observations:--Ought we to call, he says, by either of these appellations every kind of wild thick wood, encumbered with vigorous trees, upon which man has never laid his destructive hand? In that case they would be appropriate in a number of very different countries, under the Temperate, ay, and even under the Frigid Zone. But if we intend them to designate the impenetrability of an almost boundless forest, the impossibility of clearing a path with the pioneer's axe between serried ranks of trees, not one of which is less than from eight to ten feet in diameter, such virgin forests belong exclusively to tropical regions. We must not believe, however, according to the ordinary story in Europe, in the creeping parasitical lianas which, by the interlacement and entanglement of their branches, render the equatorial forests impenetrable. The lianas form but a comparatively insignificant portion of the underwood. The principal obstacle is found in the arborescent plants, which leave not a space uncovered, and this, too, in a country where all vegetables spreading over the soil become ligneous. If a traveller, as soon as he arrives in a tropical clime, whether in the continent or the islands, believes, even before he has penetrated inland, that he is transported to the heart of the virgin forests, his error simply originates in his impatience to realize a long-cherished desire. All Tropical forests are not virgin forests.