NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David Pike
Date: 2025 Feb 6, 14:10 -0800
Yes Gary
Very interesting. It does make you start wondering about the appropriateness of the use of the word ‘magnetic’ with respect to iron ore, especially magnetite. Do large areas of it act as a magnet i.e ‘hard iron effect’ because it’s been in position for so long it’s become magnetised itself, or does it simply present an easy path for the Earth’s magnetic field thus affecting local magnetic variation, similar to a 'soft iron effect'? The answer is probably 'a bit of each'. There were certainly places flying at 250 ft low level over Northern Canada when we thought ‘Funny’!
It also left me wondering what my dad did when he effectively carried a 6,000-tonne bar of the high yield stuff back from Narvick or Lulia. Presumably, he did his own heading check on each new course as would have been standard in any case. DaveP
