Abstract: A quarter hour and hour tone generator system for generating sequences of tones on the quarter hour and hour intervals. The system includes a timepiece having output means for providing a coded representation of time, means responsive to the output means for initiation of the tone generator each time the timepiece reaches a quarter hour interval. Gating means are provided for selecting a sequence of tones in accordance with the time represented by the output means. Instantaneous chime readout capability is also provided to enable en audible indication of the most recently passed quarter hour.

Abstract: An aquarium water aeration device including an upper body member having an upwardly extending tubular neck portion with a downwardly depending cylindrical skirt portion and a concentrically disposed wall portion interiorly thereof defining an annulus closed by a lower body member having a collar portion with minute axially extending serrations about the periphery thereof, the collar portion frictionally engaging within the wall portion to define minute air passageways. The annular chamber has an air inlet nipple for receiving air from an air pump, the passage of air through the air passageways directed upwardly relative to a siphon tube to which the device is connected providing a head of water to act as an airlift pump, while providing aeration to the debris-laden fluid from the aquarium into the aquarium filter to which the siphon tube is attached. A grid is connected to the lower portion of the lower body member for limiting the size of particles entering the siphon tube.