Brass Sundial Compass -Solid Brass Pocket Sundial - West London For Sale

Brass Sundial Compass - Pocket Sundial

This is a beautiful polished solid brass reproduction of an antique pocket sundial with an internal magnetic compass. The top of the sundial is hinged and a curved scale is used to set your local latitude angle. The magnetic compass allows the sundial to be oriented North. The compass features a needle lift mechanism to protect the compass's jewelled bearing when being transported. The sun's shadow cast by the sundial's vane marks the local time.

With lockable Direction compass

Size

Approximate Size 6cm X 2cm

Description :
How to Use the Pocket Sundial You will need:
A) A horizontal surface which is not close to any magnetic (or magnetisable) material.
B) To know the latitude of your location ( London is approx. 51.5 degrees North and Glasgow is approx. 56 degrees North) - but you don't need to be too accurate about this.
C) A bright sunny (not overcast) day! Note: this is not a quartz watch - at the very best it will give you the time to within a quarter of an hour. The time indicated will always be GMT not BST.

Procedure:
i) Raise the latitude quadrant (the curved brass part marked 0-60) to the vertical position.
ii) Raise the gnomon (the triangular-shaped brass piece) to the vertical position.
iii) Tilt the hinged chapter ring (the circle with the Roman numerals) to your latitude using the latitude quadrant as your index. N.B. In the British isles this will only be slightly off the horizontal.
iv) Place the instrument on the horizontal surface and orientate it so that when the compass needle comes to rest the "N" point (red) is over the North of the lower compass rose.
v) The shadow of the gnomon on the chapter ring will give you the time. That's it!