Meðan gramr, hinns svik samðit, snart Bilskirnis, hjarta, grundar fisk með grandi gljúfrskeljungs nam rjúfa.
“Whilst the ruler of Bilskirnir, whose heart did not plan treachery, quickly smashed the fish the sea-bed with the destruction of the ravine-whale”
This stanza was composed by Gamli gnævaðarskáld from the 10th century, manuscript excerpt from GKS 2367 4° (R). The verbiage in the stanza has specific sea-imagery that I find interesting.
The sequence fisk grundar, or fish of the sea-bed (fish of the ground, literally) refers to the Miðgarðsormr. It refers to the dreaded beast as a fish, which is a natural substitution for a snake.
The sequence grandi gljúfrskeljungs refers to the hammer Mjöllnir. The term gljúfr is used for an abrupt descent or chasm, most often used of wild ravine or a gully through which rivers flow, such as in árgljúfr. The compound word skeljung refers to a type of whale, possibly a humpback whale but it may also refer to a swordfish. The kenning itself refers to the Jötnar, with the hammer being the object which harms them.
The motif of Þórr fighting with sea-creatures evokes an image of a great sea battle, of which we know occurred in Hýmiskviða. This is just one variation of the story, with the others being Ragnarsdrápa, Gylfaginning, and verses in Skáldskaparmál by Bragi inn gamli Boddason, Ölvir Hnúfa, Eysteinn Valdason, and Úlfr Uggason.
Þórr siðr 