The _Rhinegold_ suffers from a plethora of undeveloped themes, some of which are treated at length as the _Ring_ proceeds. Of all announced only two remain unchanged, the Valhalla and the Fire themes. The first, I have just remarked, is not susceptible of development, and is only slightly varied throughout the _Ring_; the second does not demand development, but is varied much as Beethoven varied his melodies in his last pianoforte sonatas. The most important of those that are metamorphosed is the Spear motive. The Spear is the symbol at once of Wotan's sovereignty and of his bondage. On its shaft, the world ash-tree stem, are graven the mystic laws by virtue of which he rules; did he break these laws his power would be gone from him. The essence of the laws lies in the sanctity of compacts, and so we first hear its representative theme when the Giants come to claim Freia as payment for the building of the Burg: it makes its appearance quietly, unobtrusively, almost apologetically, and might be, as I have said, a fragment from Spohr or Weber. Its treatment in a simple snatch of two-part canon, one part following the other at half-a-bar's distance, seems like a mild gibe at those who only live for and by conventions. When it reappears in the Second Act of the _Valkyrie_ it is altogether a different thing: here we have Wotan the ruler determined at all costs to rule and using to the full the power the Spear confers on him. Like many of the greatest musical subjects, it is simple beyond the daring of the minor composers, merely an unbroken scale descending in heavy, emphatic steps to the lower octaves: it is authority personified, will that brooks no opposition. This motive, the Valhalla motive and the fire motive are the principal ones carried into the _Valkyrie_ from the _Rhinegold_; and an immense amount of new musical matter is introduced. We see no more of the inferior deities: we hear the stroke of Donner's hammer in a storm _Lied_, and Loge appears as consuming flame in the last act; but, excepting Wotan, only Fricka is seen again in human shape. The stage is now occupied by human beings, raised up, it is true, by Wotan himself, and by some other mysterious beings, also raised up by Wotan, one of whom, _the_ Valkyrie, Brünnhilda, is condemned in the final scene to become human.