
NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Dated Chart Datum
From: Bruce Hamilton
Date: 2008 Nov 03, 21:51 -0800
From: Bruce Hamilton
Date: 2008 Nov 03, 21:51 -0800
I still remember going over the charts when I made my first trip around Newfoundland and seeing that the charts were annotated with, "as surveyed by James Cook, 1775". There was no indication of any updates. The waters were deep enough that we slept well at night, but the Mate told us of meeting with an unmarked sea mount on one arctic trip. Apparently shoring up a steel hull with wood and canvas still does the trick. The work that Cook accomplished is quite amazing especially considering the equipment of the day. I just realized that I used to know the markings of the lead line, but have forgotten them completely. Was seven fathoms red bunting? I wonder how many of the world's charts are still quite out of date. I read once of a volunteer program in the UK where mariners submit the soundings from their own GPS linked sounders, and the chart makers use that data to help improve the systems. Is that really happening or was it just a plan? Oh, a little note on situational awareness. In the early eighty's, some genius in our nation's capital decided that nautical charts should be metric and for a while you could have charts with soundings in meters and feet/fathoms, as they were not replaced all at one time. We never had any groundings, but we certainly had a few unkind words to say about our chart makers as we jumped back and forth from metric to nautical soundings. I used to do the chart updates from the Notice to Mariner's and burn all the old charts when they were finally replaced. I wish I had kept them all. I could have quite a collection, and I still love paper charts! Keep a good watch. Bruce Hamilton --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To unsubscribe, email NavList-unsubscribe@fer3.com -~----------~----~----~----~------~----~------~--~---