The mountains from his bones;
The heavens from the ice-cold giant’s head.
Ymer is evidently the type of the chaos.
As the reader may be curious to know how Ymer propagated his race, I quote the following question and answer from the Vaftrudnismal. Odin in disguise interrogates, and Vaftrudner answers:
Tell me, Vaftrudner!
How did the giant of old (Ymer)
Beget children without a giantess?
Answer:
From the arm of the giant,
According to the tradition,