NavList:

George wrote, after much helpful detail about the English Channel bottom:

"What's particular interesting to me, though, is just how technically
detailed the words are. It reads almost like a pilot-book."

 

Interesting; yes, and consistent with how much navigation seems to have been effected in less technically-minded times. We know Polynesian navigators had songs which indicated their ocean voyages in some detail. Similarly, tracks across the Australian continent were known as "song paths" by the indigenous inhabitants.

 

(At the risk of incurring further George ire concerning relevance) before widespread literacy, sagas and other good tales, including navigational instructions, seem to have been commonly memorised and spread from one generation to the next, or geographically, with surprisingly little distortion.

 

A good example of this is Homer's Odyssey which seems to have been transmitted orally for several hundred years before being written down and thus frozen at that point. We know that while other myths and seemingly unrelated stories seem to have been incorporated at some stage into the tale (including, it has been postulated, a Greek trip to northern waters, perhaps even to England - relevance is creeping back!), the plain and simple sailing directions contained in the Odyssey hold good today. A number of Odyssey fans have sailed small boats around the Med, marvelling at how well the directions still work.