Four Yixing teapots and covers 19th century

Four Yixing teapots and covers 19th century, the square section bodies with incurved sides narrowing towards the neck, three decorated to one side with a raised panel of calligraphy, a smaller with incised calligraphy to both sides, each with a seal mark to the base, minor faults, 17cm max. (8) Provenance: the Arthur J Harris collection.