Ch´êng ni, lit. "pure, limpid, or clear clay," an expression which is explained in the T´ao shuo (bk. i., fol. 4 verso) as "refined earth," the word ch´êng (or ling) being equivalent to
t´ao, which means to wash.
jung ch´ê, lit. "brilliant penetrate, or brilliant right through."
[122] The age is here probably the Sung period, for we must bear in mind that the author of the Cho kêng lu is practically quoting verbatim from the Sung writer Yeh–chih.
[123] Ko ku yao lun, bk. vii., fol. 22.