From the introduction:
A strange dream invades your sleep. It begins with a view of the sea, extending to the horizon, waves gently rolling across your vision. Then, you see clouds forming, and a sinuous, black reptile, with a long body and fearsome snout, tears its way free of the waves. Floating in the air above the water, it looks about, almost as if frightened. If you are not mistaken, it appears to be a stylized dragon, not unlike those found on heraldic symbols.