The Probert Encyclopaedia of Norse Mythology

GJALP

In Norse mythology, Gjalp was a daughter of Geirrod. She was stationed at the head-waters of the fast flowing river Vimur, with her menstraul blood gushing in such quantities that the river doubled its depth from one second to the next, the object being to drown Thor who was making his way to Geirrod's castle. However, Thor noticed what was happening and hurled a boulder which plugged Gjalp's vagina and stopped the flow.
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