It might have been expected that the Incas, the boasted children of the Sun, would have made a particular study of the phenomena of the heavens, and have constructed a calendar on principles as scientific as that of their semi-civilized neighbors. One historian, indeed, assures us that they threw their years into cycles of ten, a hundred, and a thousand years, and that by these cycles they regulated their chronology.15 But this assertion--not improbable in itself--rests on a writer but little gifted with the spirit of criticism, and is counter-balanced by the silence of every higher and earlier authority, as well as by the absence of any monument, like those found among other American nations, to attest the existence of such a calendar. The inferiority of the Peruvians may be, perhaps, in part explained by the fact of their priesthood being drawn exclusively from the body of the Incas, a privileged order of nobility, who had no need, by the assumption of superior learning, to fence themselves round from the approaches of the vulgar. The little true science possessed by the Aztec priest supplied him with a key to unlock the mysteries of the heavens, and the false system of astrology which he built upon it gave him credit as a being who had something of divinity in his own nature. But the Inca noble was divine by birth. The illusory study of astrology, so captivating to the unenlightened mind, engaged no share of his attention. The only persons in Peru, who claimed the power of reading the mysterious future, were the diviners, men who, combining with their pretensions some skill in the healing art, resembled the conjurors found among many of the Indian tribes. But the office was held in little repute, except among the lower classes, and was abandoned to those whose age and infirmity disqualified them for the real business of life.16 The Peruvians had knowledge of one or two constellations, and watched the motions of the planet Venus, to which, as we have seen, they dedicated altars. But their ignorance of the first principles of astronomical science is shown by their ideas of eclipses, which, they supposed, denoted some great derangement of the planet; and when the moon labored under one of these mysterious infirmities, they sounded their instruments, and filled the air with shouts and lamentations, to rouse her from her lethargy. Such puerile conceits as these form a striking contrast with the real knowledge of the Mexicans, as displayed in their hieroglyphical maps, in which the true cause of this phenomenon is plainly depicted.17