According to "Lu Shi" records, during the Zhenguan period of the Tang Dynasty, in order to show his love for the Tang Dynasty, the chieftain of Yunnan, Mian, sent Mian Bogao to bring a batch of treasures and a very cute swan. , went to the capital to meet Emperor Taizong of the Tang Dynasty. Along the way, Mian Bogao took good care of the white swan. When he arrived at Mianyang Lake in Hubei Province, he saw that the white swan was very thirsty, so he let it go to the lake to drink water. Unexpectedly, after the white swan drank enough water, it spread its wings and flew away. Mian Bogao rushed forward, but only caught one goose feather. This made Mian Bogao very anxious. After thinking about it, he had no choice but to wrap the goose feather in brocade and write a poem. See Tang Taizong, poem;
Swans pay tribute to the Tang Dynasty,
The mountains are high and the roads are far away,
The treasure is lost in Mianyang Lake,
He fell to the ground and wailed,
Go to the Emperor of Tang Dynasty,
Please spare Mian Bogao,
Etiquette is too small for people, but intention is too important.
Goose feathers are sent from thousands of miles away.
Since then, the story of sending goose feathers as a gift from thousands of miles has been passed down.