I
Although Sicily, then, has many wonderful sights in and around it, I will meantime withdraw your mind wholly from your own province, and, passing by all questions relating to it, will direct your thoughts to a far different scene. In your society I will resume the inquiry postponed in my last book, why the Nile overflows in the summer months. Now, let me remark that the philosophers have asserted the similarity of the Danube to the Nile, because its source is unknown and it is larger in summer than in winter. Both statements are clearly false. We know for a fact that the Danube rises in Germany. Again, though the rise of the Danube begins in summer, it is at a period when the Nile still remains within its ordinary limits: the heat is then only beginning, and the stronger sun toward the latter part of spring is softening the snows, but it has to melt them before the Nile begins to rise. During the remainder of the summer the Danube actually falls until it reaches its winter size, from which in due course it begins its rise again.62