I have named, among many rivers that make music in my memory, that dirty Water of Leith. Often and Often I desire to look upon it again; and the choice of a point of view is easy to me. It should be at a certain water-door, embowered in shrubbery. The river is their dammed back for the service of the flour-mill just below so that it lies deep and darkling, and the sand slopes into brown obscurity with a glint of gold; and it has but newly been recruited by the borrowings of the snuff-mill just above, and these, tumbling merrily in, shake the pool to its black heart, fill it with drowsy eddies, and set the curded froth of many other mills solemnly steering to and fro upon the surface. Or so it was when I was young; for change, and the masons, and the pruning-knife, have been busy; and if I could hope to repeat a cherished experience, it must be on many and impossible conditions.