“We take the fertilizer, just as we can get it, and cram a cow horn with it, and bury the cow horn at depth of about half a meter, in the ground.
Thus we preserve within the cow horn the forces that the cow horn had been accustomed to exercise in the cow itself.
So it retroreflects that which is Invigorating and astral. Because the cow horn is externally surrounded by the earth, it radiates all the rays into its internal cavity, which manifest in the sense of etherization and astralization.
If you now let the ordinary manuring to connect to, I want to say, this “intellectual dung”, then you will get to see what kind of fertility may emerge out of these things.“ (Rudolf Steiner)
Source: Rudolf Steiner on Bio-dynamics in ”Spiritual Foundations for prosperity of agriculture. Agricultural Course “, complete works volume 327 (GA327, page 100)