Chinese workers have a technique to mount mortar on a roof without getting too tired. In China, workers build a house and have to mount mortar on a roof. Rather than getting tired of going up and down the ladder, they will catapult the mortar. A person is responsible for putting the material in the pocket and two others send it into the air catapulting. A worker on the roof receives the merchandise with his shovel. Original title: 非物质文化遗产