Top, what started it all: Paquet, a cargo ship captained by the author's ancestor, that got lost in  a snowstorm off Norway and sank; middle, Derek O'Reilly, a London taxi driver--the navigation and memory centers in the brains of the capital's cabbies have expanded due to their having (by law) to memorize all of London's streets; bottom, the author's sloop, which he used to emulate his ancestor's voyage--hopefully, without the fatal conclusion. 
finding north: pix