it is said that, among the duties of 'the Grand Diviner,' 'he had charge of the rules for the three Yî (systems of Changes), called the Lien-shan, the Kweî-ȝhang, and the Yî of Kâu; that in each of them the regular (or primary) lineal figures were 8, which were multiplied, in each, till the), amounted to 64.'