This very sketchy for now... sorry. Complain, if you need it expanded...
This is generally useful (I hope!), but is particularly relevant to some pages I wrote about doing your own map where the bridge crosses the river, in Haddam Connecticut.
The baseline for that map was on the dock just visible at the top left in the image above... I put a red circle around it. The red arrow is parallel to the baseline.
This page is about how you could mark "North" fairly accurately on your map, if you went to Haddam and did the work, and had forgotten to bring your "find north" compass with you, as I did.
Note also that there is a small airport in the image. The mauve line is parallel with the runway.
Note the "14" on the runway. That means that a plane taking off, starting its roll there, will be heading somewhere between 136 and 144 degrees, i.e. roughly SE, magnetic.
I leave the rest of what you need to figure out to you... but I hope it amuses you that you put the "north this way" on a map you are making without remembering to collect the necessary data the easy way. Long live lateral thinking!
Page tested for compliance with INDUSTRY (not MS-only) standards, using the free, publicly accessible validator at validator.w3.org. Mostly passes.
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