From 《
汉书·
枚乘传》and the Song collection 《
鹤林玉露》: the Song magistrate Zhang Guaiya (
张乖崖) caught a petty clerk stealing one coin per day. The clerk protested that one coin was nothing; Zhang wrote the verdict '
一日一钱,
千日千钱;
绳锯木断,
水滴石穿' — a rope saw fells a tree, a drip wears through stone.