Our Sundial Compasses are replicas of 18thC instruments and they are not just attractive desk pieces – they actually work.
Sundials have been around for centuries and are usually manufactured for a given location. As you move further from the equator, so the angle of the gnomon (the spike that creates the shadow) needs to suit the local latitude. Our replicas have an adjustable platform for the gnomon so it can be used in different locations.
Using the Sundial Compass:
1. Raise the gnomon in the centre of the platform into a vertical position and do the same with the curved latitude scale on the side of the compass.
2. Place the compass on a level surface (adjustable feet can help achieve this) so that the North marking on the base aligns with the north pointing needle.
3. Raise the circular platform so that it corresponds with the latitude for your location. Melbourne’s latitude is N37:48 so the platform will be placed between 36 and 38 on the scale.
4. Read the position of the shadow created by the gnomon on the edge of the platform and adjust for daylight saving. You now have your local time.
Correctly aligned, these instruments can be accurate within 4 or 5 minutes
This product was added to our catalog on Friday 21 January, 2011.