few figures of fishes and idols in gold and silver have been found in very ancient deposits of guano.
We can form only the most imperfect estimates of the dates of these remains. Geological evidences give no definite clew. The growth of trees over the kitchen-middens may fix dates previous to which they certainly existed, but when we have admitted the five or six centuries it took the trees from the time the wind wafted the seed to the spot, how are we to compute the number of generations of plants that were required to furnish the soil on which they could grow? One point only is ascertained, and that is that no bones of quaternary animals have been met under the kitchen-middens, and, with the exception of the figures we have mentioned, no metallic objects. The remains must, then, have been accumulated between the period of the disappearance of the larger animals and the time when the metals came into habitual use. Must we say, then, that during that long series of ages no artistic tendency revealed itself in man? Yes, if we judge by the individual objects that have been collected; no, if we attribute to that epoch the pictographs, or the figures, scenes, hieroglyphics, or rebuses, as we might call them, which are painted, engraved, and sculptured on the cliffs, the sides of caves, the bowlders, and erratic rocks, or wherever a vacant space may have been offered to the artist. Men have at all times with a childish vanity endeavored to delineate their migrations, their contests, their hunts, and their victories. Egypt has transmitted its ancient history to us on granite; the rocks of Scandinavia still wear the likeness of the Vikings' vessels; and those around the lac des Merveilles, near Nice, bear pictures of men extremely primitive in design; curious engravings have been noticed in Algeria; the Bushmen, who are among the most degraded populations of the globe, have drawn on stone, with wonderful fidelity, their hunting scenes and their loves; and the rock-paintings of New Zealand, the work also of a barbarous race, but evidently superior in execution to the scratches of the Bushmen, have been described before the London Society of Anthropology. These are isolated facts, though curious ones; but in the two Americas the number of pictographs and the extent of surface they cover give them an exceptional importance. The desire, not only to reproduce striking events, but also to give precision to their sense by conventional signs, by graphic strokes, or by hieroglyphics or phonetic or symbolical characters, is one of the most remarkable traits of the different races that have succeeded each other on the new continent. Although the initial date of these engravings is unknown, we can nevertheless affirm that they continued to be executed through many ages, and that while the most ancient ones ascend to remote epochs, in some instances these historic drawings only a little while preceded the arrival of the Europeans. Pictographs are especially abundant in the regions that formerly constituted Spanish America: in Nicaragua, near the extinct volcano of Masaya; in the