As a result, in 1810 he wrote 5 volumes of "Bukkoku Rekishohen" (literally, "study of the calendar in India") based on the astronomy of Mt. Sumeru (in Buddhism - said to be the highest mountain rising in the center of the world).
その結果、1810年（文化7年）に須弥山宇宙論による『仏国暦象編』5巻を著している。