Bob Volin wrote: > > Peter Chopelas wrote, > > <snippity> > > When I learned about nautical navigation I was surprised to learn that > > there is no need to ever concern yourself with declination because the > > charts are all set up be able to use magnetic north exclusively (perhaps > > the USGS who makes the land maps could learn something from the nautical > > charts). If you never intend to use the hand held compass for land > > navigation then absolutely you do not need or want to worry about > > declination, it would only serve to confuse you. > > Would you explain your reasoning further, Peter? I know that the compass > rose on a nautical chart shows both true and magnetic, but the hash lines > (?) on these charts are aligned to true north/south, east/west. So it seems > to me that one has to pay close attention to variation on a nautical chart. > Of course, if you have a Nav-Aid, everything is much easier (I have no > connection with the good Dr. Sutherland). A quick and dirty method which avoids this problem is to lay out parallel lines of magnetic north on 3-8 cm separations. This allows taking "good enough" *magnetic* bearings directly off the chart. I have a Weems and Plath device which resembles a monster protractor adapted to using such lines for taking accurate bearings off the chart. It is not very useful in a jouncy cockpit, but it works well the night before a paddle for laying out the bearings you expect to need. I think most of what I do is described in Burch's book. -- Dave Kruger Astoria, OR *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
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