What goes into a masterpiece is one thing. The form in which it emerges is another. What happens between, mechanics or miracle, is a third. This note is a summary statement, for a single passage in The Fall of Hyperion, A Vision, of the first of the three alone. It has developed through a series of surprises, as again and again some fact the bearing of which had been unnoticed has proved to be an element in a complex design—a design which has nevertheless achieved the effect of an effortless simplicity. It has to do, in a word, with an extraordinary convergence of impressions which, through their blendings, took form in an imaginative conception of rare beauty—a conception in which five themes interweave, almost as in a great symphonic movement: themes drawn, amazingly, from Greece, Judea, Egypt, the island of Staffa, and the Mount of Purgatory. That, I am well aware, is a statement which may not be lightly made, and warrant for it must be given.