what is discovered on board the mysterious schooner that enters the harbor?

The Russian ship Demeter is washed ashore by a terrible and sudden storm, and it is discovered that the entire crew was missing. The only body found is that of the captain, tied to the wheel and grasping a crucifix. A huge dog is seen running from the ship; the animal escapes into the woods. The ship's cargo, a great number of large wooden boxes, are handed over to a local solicitor.