Abstract: This fluid operated clock comprises a support stand which includes a shaft providing a pivot mounting for an oscillating housing, and which carries a reservoir above the housing for supplying fluid to housing inlet openings. The housing is partitioned to provide outer fluid compartments, having fluid discharge openings, and an intermediate compartment mounting an adjustable balance weight above the pivot center. The housing oscillates between defined limits and includes an actuating pin engageable with a pawl and ratchet assembly to rotate a wheel carried by the shaft and having an indicator ring attached.