Before I discovered alchemy, I had a series of dreams which repeatedly dealt with the same theme. Beside my house stood another, that is to say, another wing or annex, which was strange to me. Each time I would wonder in my dream why I did not know this house, although it had apparently always been there. Finally came a dream in which I reached the other wing. I discovered there a wonderful library, dating largely from the sixteenth and seventeenth centuries. Large, fat folio volumes, bound in pigskin, stood along the walls. Among them were a number of books embellished with copper engravings of a strange character, and illustrations containing curious symbols such as I had never seen before. At the time I did not know to what they referred; only much later did I recognize them as alchemical symbols. In the dream I was conscious only of the fascination exerted by the entire library. It was a collection of medieval incunabula and sixteenth-century prints. The unknown wing of the house was a part of my personality, an aspect of myself; it represented something that belonged to me but of which I was not yet conscious. It, and especially the library, referred to alchemy, of which I was ignorant, but which I was soon to study. Some fifteen years later I had assembled a library very like the one in the dream.