West of China, the mangonel remained the primary siege weapon until the 12th century when it was replaced by the counterweight trebuchet. In China the mangonel continued to be used until the counterweight trebuchet was introduced during the Mongol conquest of the Song dynasty in the 13th century. The counterweight trebuchet did not completely replace the mangonel. Despite its greater range, counterweight trebuchets had to be constructed close to the site of the siege unlike mangonels, which were smaller, lighter, cheaper, and easier to take apart and put back together again where necessary. The superiority of the counterweight trebuchet was not clear cut. Of this, the Hongwu Emperor stated in 1388: "The old type of trebuchet was really more convenient. If you have a hundred of those machines, then when you are ready to march, each wooden pole can be carried by only four men. Then when you reach your destination, you encircle the city, set them up, and start shooting!" The mangonel continued to serve as an anti-personnel weapon. The Norwegian text of 1240, "Speculum regale", explicitly states this division of functions. Mangonels were to be used for hitting people in undefended areas.