Two volumes: "Ten no Maki (Heaven's Volume, Part 2)" and "Chi no Maki (Earth's Volume, Part 1)" of the Kofū school's kotsuzumi (small shoulder drum) instruction manual, published in Taisho 4 (1915). Supervised by master Kōgorō Sachi and others, this is a rare edition with high value as a historical resource. Despite its age, the paper quality is firm, and it is in relatively good condition for its age.