Beyond this outer belt lay the thick shades of the central forests, where the largest trees which are produced in the two hemispheres grow side by side. The plane, the catalpa, the sugar-maple, and the Virginian poplar, mingled their branches with those of the oak, the beech, and the lime. In these, as in the forests of the Old World, destruction was perpetually going on. The ruins of vegetation were heaped upon each other; but there was no laboring hand to remove them, and their decay was not rapid enough to make room for the continual work of reproduction. Climbing-plants, grasses and other herbs, forced their way through the moss of dying trees; they crept along their bending trunks, found nourishment in their dusty cavities, and a passage beneath the lifeless bark. Thus decay gave its assistance to life, and their respective productions were mingled together. The depths of these forests were gloomy and obscure, and a thousand rivulets, undirected in their course by human industry, preserved in them a constant moisture. It was rare to meet with flowers, wild fruits, or birds, beneath their shades. The fall of a tree overthrown by age, the rushing torrent of a cataract, the lowing of the buffalo, and the howling of the wind, were the only sounds which broke the silence of nature. To the east of the great river the woods almost disappeared; in their stead were seen prairies of immense extent. Whether nature in her infinite variety had denied the germes of trees to these fertile plains, or whether they had once been covered with forests, subsequently destroyed by the hand of man, is a question which neither tradition nor scientific research has been able to resolve. These immense deserts were not, however, devoid of human inhabitants. Some wandering tribes had been for ages scattered among the forest shades or the green pastures of the prairie. From the mouth of the St. Lawrence to the Delta of the Mississippi, and from the Atlantic to the Pacific ocean, these savages possessed certain points of resemblance which bore witness of their common origin: but at the same time they differed from all other known races of men:[9] they were neither white like the Europeans, nor yellow like most of the Asiatics, nor black like the negroes. Their skin was reddish brown, their hair long and shining, their lips thin, and their cheek-bones very prominent. The languages spoken by the North American tribes were various as far as regarded their words, but they were subject to the same grammatical rules. Those rules differed in several points from such as had been observed to govern the origin of language. The idiom of the Americans seemed to be the product of new combinations, and bespoke an effort of the understanding, of which the Indians of our days would be incapable.[10]