Anti-rolling characteristics of Flume tanks are investigated by series of bench tests, results of which are analysed and expressd in terms of (C sin δ)/ω and C cos δ. Generally speaking, (1) Large anti-rolling moment is expected for large l_n/l_T ratio. (2) The frequency at peak value of (C sin δ)/ω (ω_t^') is smaller than ω_t (frequency of tank water). (3) An emprical formula for ω_t is obtained in the form ; [numerical formula]
