Picture of Mt. Sumeru

Entsū (1754-1834) was a scholarly monk of the Tendai sect in the late Edo period. He was called Mugaishi and Fumon. While Western astronomy, which espoused a geocentric theory of the universe, was spreading and the Buddhist worldview, which espoused a heliocentric theory, was declining, Entsū insisted on the Cosmic Mt. Sumeru of Indian origin, wrote the “Bukkokurekishōhen” and other works, and devised his own ritual instruments such as the Shumisengi (model of Mt. Sumeru) and Shukushōgi (model of Shrunken elephant) that visually expressed Buddhist astronomical theories.

Entsū’s Buddhist astronomy was passed on to his disciples Kanchū Zenki and Kōgan. Later, at the request of both of them, Tanaka Hisashige produced a mechanically operated Shumisengi. It is said that construction began in Kōka 4 (1847) and was completed in Kaei 3 (1850).

This drawing is based on a woodblock print showing a diagram and explanation of the Shumisengi, published in Bunka 10 (1813) as “Shumisengi Mei narabini Jo,” with words of wisdom by Kanchū Zenki and Kōgan. At the center of the world is a huge mountain called Mt. Sumeru, which is alternately surrounded by the sea and mountains. The outermost mountain, called Tetchisen (Iron Encircling Mountains), is at the edge of the world, and the ocean inside Tetchisen is made up of islands of various sizes. Four particularly large islands are depicted in the east, west, south, north, and south directions, and the island depicted in the south (to the lower right of Mt. Sumeru) is the Jambudvipa, where humans live.

At the top is Entsū’s preface, and below it are the Shikigo (a record of the date) of Kanchū (Kōka 4 [1847] ) and Kōgan (Kaei 1 [1848] ). Kanchū commends the achievements of his teacher Entsū, while Zenki describes the history of Buddhist astronomical theory. Kanchū’s and Kōgan’s comments may have been contributed at the time of the reprinting. Or, since they are from Kōka 4 (1847) and the year following Kaei 1 (1848), they may be related to Tanaka Hisashige’s construction of the Shumisengi.