Although the ruins of a kiln used to create the Qin terracotta warriors and horses, which are celebrated as the Eighth Wonder of the World, have not yet been found, academics believed that the terracotta warriors and horses were fired in a kiln made from an upright pit. Now, after 20 years of unremitting research, professor Ye Hongming, a famous ceramics expert, has finally hypothesized a new method of firing the terracotta warriors and horses. He suggests that the terracotta warriors and horses were probably not fired in upright kiln pit after all.
Professor Ye Hongming, director of the National Ancient Ceramics Committee, has successfully unlocked the secret of firing the official pottery and porcelain of the Southern Song Dynasty (1127-1279). After examining fragments of the terracotta warriors and horses, Ye Hongming noticed that although the terracotta warriors and horses are characterized by hardness, they may well have been successfully fired using a traditional temporary kiln technique, not necessarily a kiln stove as previously thought.
The whole firing processes probably involved many steps. First, the potters would have created a complete mold of a pottery figurine. After the pottery figurine had dried in the shade, the potters would have heaped the cast with tinder, made from sawdust and cob, surrounding the mud figurine from head to toe and also filling its interior. Grass would then have been used to create an outer cast which would provide the fuel for firing the mud figurine. Potters would then apply mud to the outside of the grass creating a temporary shell which would stop the thick mud figurine embryo from cracking as the temperature quickly rose. Once the temperature had climbed to its maximum heat, the mud surface of the kiln shell would crack due to desiccation. Air would have entered the figurine increasing the temperature and glazing rate. Once enough air had entered the temporary kiln shell and the wood had been sufficiently burnt, the mud would crack leaving the completely formed terracotta warriors and horses.
(china.org.cn by Wu Nanlan, October 12, 2002)