In Ibuki Island, Kagawa Prefecture, a "kako-shiki (declining)" accent is observed by some scholars. Judged with the aural impressions, the previous studies have stated that this accent pattern has subtle declining tone from the second mora to the third mora. In this article, we measure frequency movements of this accent and compare them with those of the words in the second mora nucleus type accents. The result is as follows. The difference clearly exists between the kako-shiki accent and the other accents on Ibuki Island. And the peak position of frequency movement does not always exists between the second mora and the third mora. In addition, we collect samples of the small declining tones in three different places in the northeastern Shikoku area. We try to extract frequency movement patterns in each mora, and to characterize these patterns.
