The Yongle Bell was cast by means of China' s traditional method of pit shaping and pottery moulding. No characters cast on the bell were left out by mistake and the lines were well spaced, manifesting the effects of refinement and neatness. First of all, the special clay mould material was filtered through water over and over again, so it was finer than water-glass sand. Clay moulds were made by scraping, divided into pieces and dried in the shade. Characters were written on Xuan paper (a kind of high- quality paper for traditional Chinese painting and calligraphy) after typesetting planning. The Xuan paper was pasted on the mould and the characters were copied out and then carved by engravers. When the moulds were combined for casting, each mould had to be preheated to effect "surface pottery moulds." When the surface strength of pottery moulds was increased in the process of casting, no damage would be caused to the cast. The inscriptions on the Yongle Bell to-talled more than 230,000 characters. Not a single character was cast in a wrong way. This alone was astonishing.