Odin's sacrifice

I ween that I hung on the windy tree,
Hung there for nine nights full nine;
With the spear I was wounded, and offered I was,
To Othin, myself to myself,
On the tree that none may know
What root beneath it runs.
None made me happy with a loaf or horn,
And there below I looked;
I took up the runes, shrieking I took them,
And forthwith back I fell.

Havamal, transl. Henry Adam Bellows