Now will I spur again my wit, and use Poetic skill to weave words into song, telling of one among the race of fish, the great asp-turtle. Men who sail the sea often unwillingly encounter him, dread preyer on mankind. His name we know, the ocean swimmer, Fastitocalone. Dun, like rough stone in color, as he floats he seems a heaving bank of reedy grass along the shore, with rolling dunes behind, so that sea-wanderers deem their gaze has found an island. Boldly then their high-prowed ships they moor with cables to that shore, a land that is no land. Still floating on the waves, their ocean-coursers curvet at the marge; the weary-hearted sailors mount the isle, and, free from thought of peril, there abide.
Elated, on the sands they build a fire, a mounting blaze. There, light of heart, they sit – No more discouraged – eager for sweet rest. Then when the crafty fiend percieves that the men, camped upon him, making their abode, enjoy the gentle weather, suddenly under the salty waves he plunges down, straight to the bottom deep he drags his prey; he, guest of ocean, in his watery haunts drowns ships and men, and imprisons them within the halls of death. – The Old English Physiologus
This tale is taken from the Physiologus – A medieval bestiary dated back to Alexandria in the 2nd century AD that enjoyed huge popularity in Europe throughout the Middle Ages. It tells the tale of the Asp-Turtle (Greek: Aspidochelone) or Fastiocalone, a sea dwelling creature so giant, and so ancient, that trees and shrubbery have sprouted from his thick hide. Upon seeing this mass rising out of the ocean, weary sailors assume it to be land and happily scurry upon it hoping for some rest from the unforgiving ocean. The asp-turtle waits, aware of the trespassers on his back, until they are settled and lulled into a false sense of security. He cunningly knows when this is, when he feels the burning flames of the men’s fires upon his skin and drags them down to a watery grave.
In the 6th Century the Irish Monk, St Brendan, found a similar creature during his famed seven-year sea voyage. In search of the Blessed Isle (Paradise), he sets sail in a round boat made of leather with 14 followers (3 more join last minute) and heads out on his mission. At one of the little islands, they stop at, Brendan’s men get out to boil a cauldron of fish, but as they light the fire the whole island begins to tremble and shake. The men retreat quickly back to the ship, just as they island takes off, swimming through the ocean, their little fire still alight on its back. Looking to St Brendan, he explained that they had found Jasconius, the biggest fish in the world, a fish that spends all of its time attempting to put his tail in his mouth, a frustratingly unachievable feat due to his own great bulk.
St Brendan on the back of Jasconius
In the One Thousand and One Nights, during the first journey of Sinbad the Sailor, he and his men also mistake a gigantic whale for an island when they see the trees that have taken root upon it. They settle down and make camp, but the fires they have lit on the creature’s back rouse it from its sleep, and the whale dives below the ocean to quench the flames, taking Sinbad with it. While Sinbad fails to tell us the name of this creature, in Middle Eastern lore the giant monster was known as Zaratan.
Among the Inuit of Greenland, the sea monster is known as Imap Umassoursa, and features in their legends and lore. Many fisher-folk are said to be trepidatious of sailing through shallow waters found out in the ocean in case it is the Imap Umassoursa rising from the deep. No one wants their boat to be caught on his back as he surfaces, fearing they will be thrown overboard and perish in the freezing waters.
While I’m no sailor, one can only imagine that after days, months, or possibly years at sea the thought of getting off the ship and having a night where you were not at the mercy of the mercurial ocean, a night where you could let down your guard and sleep peacefully, would be a welcome relief. To have that island rear its head, and the land beneath your feet torn asunder, seems like a cruel trick of fate, too cruel even by the standards of the harsh mistress that is the sea.
Physiologus: A Medieval Book of Nature Lore
The Voyage of Saint Brendan: The Navigator
Giants, Monsters, and Dragons: An Encyclopedia of Folklore, Legend, and Myth