Mercury is like solid water, nothing can happen without it, because it has the power of spiritual Blood, and when combined with the Body, it changes thanks to the addition of Spirit. And thusly, reduced to just the One, they change one into another, because the Body embodies the Spirit, and the Spirit transforms the Body into the Spirit, bestowing colours and tinting it with Blood, because everything the Spirit owns also has Blood, and Blood is the spiritual moisture that strengthens Nature.
Nicolas Flamel