It was apparent that the channel had been created by water filling the crack of a seismic fault.
Gregg Andrew Hurwitz MINUTES TO BURN (2001)
After 300 days he escaped, again by water.
2019, 'A Journey to St. Helena, Home of Napoleon's Last Days', Smithsonianhttps://www.smithsonianmag.com/travel/journey-st-helen-home-napoleon-last-days-180971638/