Star Gauge

The Star Gauge (Chinese: 璇璣圖; pinyin: xuán jī tú), or translated as "the armillary sphere chart", is the posthumous title given to a 4th-century Chinese poem written by the Sixteen Kingdoms poet Su Hui for her husband. It consists of a 29 by 29 grid of characters, forming a reversible poem that can be read in different ways to form roughly 3,000 smaller rhyming poems.^[1] The outer border forms a single circular poem, thought to be both the first and the longest of its kind.