"I know nothing in the visible world that combines splendour and purity so perfectly as a great mountain entirely covered with frozen snow and reflected in the vast mirror of a lake. As the sun declines, its thousand shadows lengthen, pure as the cold green azure in the depth of a glacier's crevasse, and the illuminated snow takes first the tender colour of a white rose, and then the flush of a red one, and the sky turns to a pale malachite green, till the rare strange vision fades into ghastly gray, but leaves with you a permanent recollection of its too transient beauty."[7] Wallace especially, and very justly, praises the description of tropical forest scenery given by Belt in his charming _Naturalist in Nicaragua_:-- "On each side of the road great trees towered up, carrying their crowns out of sight amongst a canopy of foliage, and with lianas hanging from nearly every bough, and passing from tree to tree, entangling the giants in a great network of coiling cables. Sometimes a tree appears covered with beautiful flowers which do not belong to it, but to one of the lianas that twines through its branches and sends down great rope-like stems to the ground. Climbing ferns and vanilla cling to the trunks, and a thousand epiphytes perch themselves on the branches. Amongst these are large arums that send down long aerial roots, tough and strong, and universally used instead of cordage by the natives. Amongst the undergrowth several small species of palms, varying in height from two to fifteen feet, are common; and now and then magnificent tree ferns send off their feathery crowns twenty feet from the ground to delight the sight by their graceful elegance. Great broad-leaved heliconias, leathery melastomae, and succulent-stemmed, lop-sided leaved and flesh-coloured begonias are abundant, and typical of tropical American forests; but not less so are the cecropia trees, with their white stems and large palmated leaves standing up like great candelabra. Sometimes the ground is carpeted with large flowers, yellow, pink, or white, that have fallen from some invisible tree-top above; or the air is filled with a delicious perfume, the source of which one seeks around in vain, for the flowers that cause it are far overhead out of sight, lost in the great over-shadowing crown of verdure."