There is a tradition that about two thousand years ago a complete stone chime was found in a pool, and that this model was followed by imperial decree. But this, if correct, does not afford any accurate guidance or tell us what kind of stone chime was extant during the old Hsia, Shang, or Chou dynasties; for not an instrument or book of those periods escaped the great destruction ordered by the Emperor Che Huang-ti; at least, there is no certain evidence against this belief. So that, for the determination of the actual date of the introduction of the supposed equal tempered twelve semitone scale, we remain in the dark, without a clue. Moreover, when the existing stone chimes—or, rather, the _Yün-lo_, or gong chimes constructed to correspond in scale to the stone chimes upon the same twelve _lüs_ principle—are submitted to examination of the necessary rigid enquiry by tests, they do not bear out the true semitonal character that has been asserted. Mr. Ellis tested two specimens in the South Kensington Museum, but both differed greatly, and he failed to find anything like the assumed scale; and such scale as he did find he was unable to give any theory for. Van Aalst says that It has become exceedingly difficult to find a _Yün-lo_ capable of giving a satisfactory gamut; besides, the pitch is not uniform, so that two _Yün-los_ rarely agree. And of the _Pien-ching_, or stone chimes, he states that It is exclusively used in court and religious ceremonies, and it would be considered a profanation to use it elsewhere. It is impossible to find a complete instrument for sale, although separate stones may be found. It is not known to whom and to what dynasty the _Pien-ching_ may be attributed, but there is no doubt that it is one of the most ancient instruments. Where then shall we find this semitonal scale, this twelve notes series comprised within the octave? Considering how very ancient the stone chime is, the question may well arise how the pitch was derived or ascertained, since in the material and dimensions no certain reliance could be placed. Both the stone chime and the _Sheng_ are attributed to an era some five thousand years ago (about the time of Noah), and then in those days the Chinese had long been a musical people. It would be but natural to conclude that the _Sheng_ conforms most to the _lüs_ the ancient and the original determinant of pitch, and we may be quite sure that the pitch given by my pipe is the same to-day as in that remote age. Neither strings nor stones can pretend to the same absolute fixity.