NavList:

>>I believe that there are modern day  Admiralty charts of the Great Barrier Reef that still contain sounding measurements taken by a certain William Bligh - after the mutiny while he was navigating the open launch.<<

Wow!

Combining Bligh's inability to determine his longitude with the reality that a coral reef can grow vertically by 16 feet/century (Calder, op. cit., p. 29), that makes these uncharted waters, even if you have soundings indicated on a chart.

Seems like sailing through this region today would be a matter of white-knuckles on the tiller.  I can hardly imagine it.

I just read Bernard Moitessier's book, The Long Way. In it, he mentions a single-hander friend of his who arranged lines and blocks so he could climb up the steps on his mast to the spreaders and - sailing with club-footed jib and main - steer his way around coral heads by looking at the color of the water.

Moitessier speaks, by the way, of being thoroughly chilled on deck, down in the "roaring 40s", sextant in hand, waiting hours trying to catch a brief glimpse of the sun through the clouds. The book is interesting, and Moitessier is certainly...unique.  He entered a single-handed, non-stop, round-the-world race in 1968, starting in England, around the Cape of Good Hope, Cape Leeuwin, and Cape Horn.  When he got to the south Atlantic, he decided he would prefer to abandon his wife and children back in France and keep on going...so he passed Good Hope and Leeuwin again, to finish in Tahiti.

Oddly enough, through 10 continuous months of sailing, he said he took only a couple of star sights.  He did all his navigation with sun sights.  He was able to get time signals via radio.

Bob