gnome-control-center/capplets/screensaver/screensavers/bubbles.xml

<?xml version="1.0" encoding="ISO-8859-1"?>

<screensaver name="bubbles">

    <command arg="-root"/>

    <number _label="Speed of Motion." _low-label="Faster" id="delay"
            type="slider" default="2" arg="-delay %" low="1"
            _high-label="Slower" high="500000"/>

    <boolean _label="Draw circles instead of pixmap bubbles."
             arg-unset="" id="simple" arg-set="-simple"/>

    <boolean _label="Don't hide bubbles when they pop." arg-unset=""
             id="broken" arg-set="-broken"/>

    <boolean _label="Bubbles exist in three dimensions." arg-unset=""
             id="3d" arg-set="-3D"/>

    <boolean _label="Display screensaver in monochrome." arg-unset=""
             id="monochrome" test="mono" arg-set="-mono"/>

</screensaver>