《徐霞客游记·滇游日记三》
广西省的山只有石头，所以有很多从洞穴穿流出来的河流，而且河水全都清澈见底。
惟抚仙湖最清。粤山惟石，故多穿穴之流，而水悉澄清。
The mountains in Guangxi province contain only stone, so there are many rivers that emerge from caves, and all the river water is crystal clear.