Universal equinoctial armillary dial for latitudes 0°-90° North. The base is supported by three levelling screws and features a zodiacal scale and a date scale. Within these scales, the circular plate supporting the dial is free to rotate. At the centre of the plate is a compass. The four legs of the dial support, set on the circular plate, meet above the compass. Two opposite ones have metal pointers riveted to the circular plate at their base, which move over the date scale. These legs carry the meridian scale for setting the latitude.

A horizontal ring sits on top of the vertical degree scales. This is used to tell the time in places with a different longitude. A rotatable outer ring with an hour-circle is set on top of the main ring. A fixed disc set inside this carries a degree scale. Set within this framework of rings is an armillary dial, which can be lifted out of the instrument. On its meridian ring are degree scales and a list of places with their latitudes. Pivoted within the meridian ring is the axis of the world. Three further rings are set around this axis and are free to rotate. One of these is cut through to allow the sun's rays to shine through it.

This dial is the most complicated of the three Hauser and Polanski dials. The time-telling part of the instrument is supplied by a three-ring universal equinoctial ring dial set at the top of the instrument; this part can also be removed to be used as a separate instrument. On its base, the dial is signed 'Invent . Per . Mathiam . Havser . Bernard . Polanski . Fecit .'

For more information regarding this dial please refer to the OUP & NMM catalogue, 'Sundials at Greenwich'.