 On the 8th expedition they covered over 13,000 km in 914 days, most of it in Kyushu.By this time Ino was 70 years old, which was decades older than the average lifespan at that time.In addition to his maps, Inō produced scholarly works on surveying and mathematics, including "Chikyū sokuenjutsu mondō" and "Kyūkatsuen hassenhō".