by silk reserves and founded a Department responsible for destroying old notes. Yelu Chucai protested to Ögedei that his large-scale distribution of appanages in Iran, Western and North China, and Khorazm could lead to a disintegration of the Empire. Ögedei thus decreed that the Mongol nobles could appoint overseers in the appanages, but the court would appoint other officials and collect taxes. The Khagan proclaimed the Great Yassa as an integral body of precedents, confirming the continuing validity of his father's commands and ordinances, while adding his own. Ögedei codified rules of dress and conduct during the kurultais. Throughout the Empire, in 1234, he created postroad stations (Yam) with a permanent staff who would supply post riders' needs. Relay stations were set up every 25 miles and the yam staff supplied remounts to the envoys and served specified rations. The attached households were exempt from other taxes, but they had to pay a qubchuri tax to supply the goods. Ögedei ordered Chagatai and Batu to control their yams separately. The Khagan prohibited the nobility from issuing paizas (tablets that gave the bearer authority to demand goods and services from civilian populations) and jarliqs. Ögedei decreed that within decimal units one out of every 100 sheep of the well-off should be levied for the poor of the unit, and that one sheep and one mare from every herd should be forwarded to form a herd for the imperial table. Karakorum From 1235–38 Ögedei constructed a series of palaces and pavilions at stopping places in his annual nomadic route through central Mongolia. The first palace Wanangong was constructed by North Chinese artisans. The Emperor urged his relatives build residences nearby and settled the deported craftsmen from China near the site. The construction of the city, Karakorum (Хархорум), was finished in 1235, assigning different quarters to Islamic and North Chinese craftsmen, who competed to win Ögedei's favor. Earthen walls with 4 gates surrounded the city. Attached were private apartments, while in front of stood a giant stone tortoise bearing an engraved pillar, like those that were commonly used in East Asia. There was a castle with doors like the gates of the garden and a series of lakes where many water fowl gathered. Ögedei erected several houses of worship for his Buddhist, Muslim, Taoist, and Christian followers. In the Chinese ward, there was a Confucian temple where Yelu Chucai used to create or