A clock generator having a delay locked loop and a delay control circuit. The implants are joined by a connector. The arch has openings therethrough for dispensing bird feed from the storage compartment onto the base. A pressure switch or thermostat is provided for operating the boiler and the supply valve on the supply conduit for supplying water to the boiler to permit water to be added every time the heater is energized. By controlling the compositions of the materials indium-gallium-arsenic-nitride and gallium-arsenide-antimonide, and by changing the thickness and order of the layers, the new material would possess a specific energy gap, which in turn determines the base-emitter turn-on voltage of the heterojunction bipolar transistor. The metering device includes an upper chamber, a lower chamber coupled to the upper chamber, a piston selectively moveable within the upper chamber and the lower chamber and a valve providing selective fluid communication between the lower chamber and the reservoir in response to movement of the piston.