In the hour of evening, under a wintry sky amid whose darkly massed vapours a young moon is peering down upon this maddened world, I wander alone through deserted roadways towards that old solitary brick-tower. Here I stand, and watch the Arno rolling its sullen waves. In Pisa, at such an hour, the Arno is the emblem of Despair. Swollen with melted snow from the mountains, it has gnawed its miserable clay banks and now creeps along, leaden and inert, half solid, like a torrent of liquid mud--irresolute whether to be earth or water; whether to stagnate here for ever at my feet, or crawl onward yet another sluggish league into the sea. So may Lethe look, or Styx: the nightmare of a flood. There is dreary monotony in all Italian rivers, once they have reached the plain. They are livelier in their upper reaches. At Florence--where those citron-tinted houses are mirrored in the stream--you may study the Arno in all its ever-changing moods. Seldom is its colour quite the same. The hue of café-au-lait in full spate, it shifts at other times between apple-green and jade, between celadon and chrysolite and eau-de-Nil. In the weariness of summer the tints are prone to fade altogether out of the waves. They grow bleached, devitalized; they are spent, withering away like grass that has lain in the sun. [4] Yet with every thunder-storm on yonder hills the colour-sprite leaps back into the waters. Your Florentine of the humbler sort loves to dawdle along the bank on a bright afternoon, watching the play of the river and drawing a kind of philosophic contentment out of its cool aquatic humours. Presently he reaches that bridge--the jewellers' bridge. He thinks he must buy a ring. Be sure the stone will reflect his Arno in one of its moods. I will wager he selects a translucent chrysoprase set in silver, a cheap and stubborn gem whose frigidly uncompromising hue appeals in mysterious fashion to his own temperament. Whoever suffers from insomnia will find himself puzzling at night over questions which have no particular concern for him at other times. And one seems to be more wide awake, during those moments, than by day. Yet the promptings of the brain, which then appear so lucid, so novel and convincing, will seldom bear examination in the light of the sun. To test the truth of this, one has only to jot down one's thoughts at the time, and peruse them after breakfast. How trite they read, those brilliant imaginings!