At last, to your immense satisfaction, find yourself at the Liusnan River. From this part
of the forest to the sea, the distance is three miles. Here and there in the woods lie blood-
red stones, or rather stones that appear to be partially stained with blood. Pick one up.
On rubbing it, find the color merely external, and perfectly distinct from the stone itself.
It is, in fact, Byssus jolithus.
In this way, work always to uncover the tricks of nature.