Fu-hi, Shön-nung and Huang-ti represent a group of rulers comprised by the Chinese under the name of _San-huang_, i.e. "The Three Emperors." Although we have no reason to deny their existence, the details recorded concerning them contain enough in the way of improbabilities to justify us in considering them as mythical creations. The chronology, too, is apparently quite fictitious; for the time allotted to their reigns is much too long as a term of government for a single human life, and, on the other hand, much too short, if we measure it by the cultural progress said to have been brought about in it. Fu-hi's period of hunting life must have lasted many generations before it led to the agricultural period represented by the name Shön-nung; and this period in turn could not possibly have led within a little more than one hundred years to the enormous progress ascribed to Huang-ti. Under the latter ruler a regular board of historians is said to have been organized with Ts'ang-kié as president, who is known also as Shi-huang, i.e. "the Emperor of Historians," the reputed inventor of hieroglyphic writing placed by some authors into the Fu-hi period and worshipped as Tz'ï-shön, i.e. "God of writing," to the present day. Huang-ti is supposed to have been the first builder of temples, houses and cities; to have regulated the calendar, to which he added the intercalary month; and to have devised means of traffic by cars drawn by oxen and by boats to ply on the lakes and rivers of his empire. His wife, known as "the lady of Si-ling," is credited with the invention of the several manipulations in the rearing of silkworms and the manufacture of silk. The invention of certain flutes, combined to form a kind of reed organ, led to a deeper study of music; and in order to construct these instruments with the necessary accuracy a system of weights and measures had to be devised. Huang-ti's successors, Shau-hau, Chuan-hü, and Ti-k'u, were less prominent, though each of them had their particular merits.