The "Ur" rune

I have recently started to look through Thomas Karlsson book "Uthark - nightside of the runes" again. My interest grew as I came to the part where he explains the "ur" rune. Look at this:

Ur (u): The Ur rune denotes the primeval state and the origin. The Ur rune is the Ur (original)-ox or the Ur-cow which in many mths represent the state before creation. In Nordic mythology it is the cow Audhumbla. If we were to turn the Ur rune so that it would look like a normal "u" we can see how it illustrates the horns of the animal. From the udder of Audhumbla four rivers of milk are flowing, feeding the other primeval being Ymer. The rivers of milk are the inherent nourishing force of the original state that spreads out in the cardinal directions of space. From a saltstone clad with white frost Audhumbla licks out the god triad of Voden, Vile and Ve. The saltstone is the crystal shaped form in which gods and runes can be found. This is the potentiality of the original state which is actualized and manifested through the following runes of the Uthark. The crystal returns to the Hagal rune. The Ur rune also illustrated Ginnungagap, the wide-open crack of primeval chaos and the original emptiness. The Ur-rune is the womb from which everything is created and born.

Very interesting isnt it? I find it very inspiring to see its relation to other koncepts in different traditions around the world.