RomeoMike wrote:



I suppose that the term declination would better be unused in favor of
"variation" in the context of defining the difference between magnetic
and true north, and in my experience it is unused in aviation.
Unfortunately, it is used on government issued topo maps and in some
orienteering books and by some orienteering compass makers, who tell one
to enter the "declination" into the compass card so that the needle
points to true north. Inclination is another term with different meaning
in different contexts.


OK, before I get flamed, I know that the compass needle always points to
magnetic north, but on an orienteering compass the "declination" is set
in the compass card so that the north indication is under the needle.