NavList:

Dear Bob,

I experimented with a (supposedly "viking-style") Sun-compass which is much easier to build.

When the weather|environment permits - it workds just fine, as accurate as a good magnetic compass (accounting for the current value of magnetic declination). I checked it on a sea shore by comparing the N-S line orientation with the actual direction to the Polaris in the evening.

All you need is the gnuplot package, a bit of level cardboard and a dressmaker's pin (with a spherical top, that's important as a "shadow sharpener" feature).

Placing the printed scale horizontally and sticking-in the pin vertically according to the pre-computed pin length|height you must rotate the assembly untill the center of the shadow is exactly on the line. At that moment the N-S line is properly aligned with the N-S geographic direction. And as a by-product you will know the Local Apparent Time. No external source of time is necessary! :)

The PLT file (for my last year experiment) is attached, you will need to update the GHA|Dec table accordingly.

Warm regards,

Tony

60°N 30°E