
Fifteen-Piece Tangram Puzzle

A sword made from the fifteen pieces

The fifteen pieces form a square
Almost fifty years after the publication of the first known tangram book, Tong Xiegeng (1828-1899), a scholar-official from Hangzhou, invented a new dissection of the square into fifteen pieces. Tong called his new pieces enhancing intelligence pieces (yizhi ban 益智板), and he devoted the rest of his life to creating elegant constructions with them.
Unlike banquet tables, butterfly tables and the older seven-piece tangram, this new fifteen-piece construction set contained pieces with curved edges. The larger number of pieces, including the six curved pieces, gave the fifteen-piece tangram puzzle greater versatility than its predecessors and allowed the construction of more accurate and expressive images. Making use of his knowledge of poetry, literature, calligraphy and painting, Tong formed arrangements of the pieces to illustrate passages from literary sources.

Tong Xiegeng holding one of his treasured mirrors
Tong based his fifteen pieces on the doubling number sequence 1, 2, 4, 8 of the Book of Changes, with the numbers in this sequence physically represented by one parallelogram, two semicircles, four corners and eight polygonal members of pairs that make up the set. The sum of 1, 2, 4 and 8 is, of course, 15.
In 1862, Tong Xiegeng finished writing the first draft of his two-volume Enhancing Intelligence Diagrams (Yizhi tu 益智图). The first volume contains outlines of elegant fifteen-piece puzzle constructions illustrating passages from poetry and classical writings. The second volume has outline illustrations of scholar’s items and several Chinese characters along with poetic descriptions.
Enhancing Intelligence Diagrams enjoyed great success; however Tong Xiegeng received stinging criticism from some individuals who looked down upon his work and stated that his talent would be better spent on traditional scholarly pursuits than on “trivial things.” In 1880, Tong answered his critics in a statement entitled “Undoing the Ridicule,” in which he argued that his fifteen-piece tangram puzzle “provides a new means of entertainment for people of intelligence and girls from well-to-do families.” Tong concluded by defiantly stating, “I will not study those established arts, following in the dust of others and picking up the spit from other people’s talk.”
![]() 1 parallelogram, 2 semicircles |
![]() Boat arriving |
![]() “Raising my cup, |

Pages from Tong Xiegeng’s Enhancing Intelligence Diagrams of One Thousand Characters, 1892
In 1885, Tong Xiegeng published two more volumes of fifteen-piece puzzle constructions, Additional Enhancing Intelligence Diagrams. The second of these volumes has illustrations of Chinese characters to construct using the fifteen pieces. Evidently, this volume proved to be very popular, because after its publication Tong embarked on his most ambitious project—using the fifteen pieces to form each of the 1000 characters in the Liang dynasty (502-557) classic literacy primer Thousand Character Essay. He completed this project in 1892 with the publication of Enhancing Intelligence Diagrams of One Thousand Characters.
The fifteen-piece tangram puzzle and its use to portray so many aspects of Chinese culture was essentially the work of one man, Tong Xiegeng. If the banquet tables, butterfly tables and seven-piece tangram are considered to be the first three generations of Chinese geometrical shape-making puzzles, then the fourth generation must surely be Tong’s fifteen-piece tangram puzzle.
Tong Xiegeng died in 1899, but his fifteen-piece tangram puzzle books continued to be extremely popular. His son Tong Danian assumed responsibility for publication of his father’s works and began a long relationship with Shanghai’s leading publisher, Commercial Press. Tong Xiegeng’s books were in such great demand that Commercial Press reprinted a six-volume collection year after year and also produced sets of the fifteen pieces to accompany the books. However publication of Tong Xiegeng’s books ceased in 1933 as life in Shanghai deteriorated during the prelude to Japan’s full-scale invasion.
Today Tong Xiegeng’s family continues to honor his work. One great-grandson has the family’s collection of Tong Xiegeng’s books that survived China’s war with Japan, the civil war, and the Cultural Revolution. And another great-grandson runs a web site with an online version of the fifteen-piece tangram.
The Fifteen-Piece Puzzle in the Imperial Household

Prince Gong, 1860
In addition to its popularity among scholars and school children, members of the imperial family also enjoyed the fifteen-piece tangram puzzle. The American missionary and teacher, Isaac Taylor Headland, wrote, “It is a toy for children, a puzzle for grown folks, but it is used by all classes, from the dowager princesses to the little boys and girls in the homes of the common people.”
Prince Gong (1833-1898), the sixth son of the Daoguang Emperor, was in charge of China’s government during the 1860s and 1870s. Prince Gong was a fifteen-piece tangram aficionado and owned a set of small, perfectly formed ivory pieces in a brass box with a sliding lid. In 1892, he wrote an inscription in Tong Xiegeng’s Enhancing Intelligence Diagrams of One Thousand Characters.

Prince Gong’s inscription praising Tong Xiegeng’s work as a new method of calligraphy
Pu Yi (1906-1967), the last emperor of China, played with the fifteen-piece tangram puzzle during his childhood in the Forbidden City. His set, which remains in the palace’s warehouse, is not at all fancy and could very well have come from a nearby department store or bookstore. The fifteen wood pieces are arranged in a square wood box with a sliding lid. Painted in white on the lid are the characters 益智圖 (enhancing intelligence diagrams).

Pu Yi, the last emperor of China, and his fifteen-piece tangram puzzle
Courtesy of The Palace Museum, Beijing
The Forbidden City also has a six-volume set of fifteen-piece tangram puzzle books with a set of small pieces inset into its cardboard case. These books were published in 1897 and are still in the palace’s library, although the cardboard case is now full of wormholes and the fifteen original pieces have been replaced by crude wood copies.
References
Isaac Taylor Headland. The Chinese Boy and Girl. New York, 1901.
Tong Xiegeng. Yizhi tu (Enhancing Intelligence Diagrams). Hulin [Hangzhou], 1878.
Tong Xiegeng. Yizhi xu tu (Additional Enhancing Intelligence Diagrams). Hulin [Hangzhou], 1885.
Tong Xiegeng. Yizhi tu qianziwen (Enhancing Intelligence Diagrams of One Thousand Characters). Shanghai, 1923.





