Felt rug with floral motif. Various colors of sheep’s wools or animal hairs are laid out in a pattern and then covered with a layer of ground-color wool. The whole is rolled up in a mat and felted together by adding a weak alkaline solution and applying friction and pressure to the fibers till they mesh tightly. Rugs of this sort were made in Central Asia, and traveled through China to Japan. The Shōsō-in has 37 such rugs. Plain color felt rugs are called shikisen.