The Odyssey, Book 19:
“Ah my friend,” seasoned Penelope dissented,
“dreams are hard to unravel, wayward, drifting things-
not all that we glimpse in them will come to pass..
two gates there are for our evanescent dreams,
one is made of ivory, the other made of horn
those that pass through the ivory cleanly carved
are will-o’-the-wisps, their message bears no fruit,
The dreams that pass through the gates of polished horn
Are fraught with truth for the dreamer that can see them."
Book 19, Translated by Robert Fagles.
Surely the most beautiful passage in the Odyssey?
Hundreds of years later, Virgil describes a tree that grows in the terrifying entranceway of Hades;
"a huge dark elm" with "ancient arms, the resting place ... of flocks of idle dreams, one clinging under every leaf" (the Aeneid, Book 6).
Instead of looking for the Loch Ness monster, (which we all know to exist, anyway, 'scientific' opinion on the matter being no more than an ambiguously desperate cover-up) perhaps explorers should set off to the remote corners of the globe to find this ancient dream-architecture, this tree and these gates of horn. For Virgil's tree, the caverns at Cumae, found today on the bay of Naples (and home of our old friend the Sybil), are said to lead to the Greco-Roman underworld. So they could start by running that terrifying gamut, if they dared.
Those exquisitely described horns, though, could be anywhere, they are only described by Penelope, never seen by Odysseus on his travels. And given the controversy over exactly where the Acheans sailed to and from in the Odyssey, (Greenland, the North Pole, Asia Minor, Cilicia, Zembla?) it's impossible to pinpoint even where they definitely aren't. They may equally be nowhere other than inside Penelope's head, a Greek woman dead for at least 2,700 years. I like to imagine them hovering over the sea in some undiscovered Arctic region, next to the bones of Captain Oates, still trapping and guiding our 'evanescent dreams'.