But that certain something of the preternatural in the scene, of which he could not rid his mind:--the, so to speak, voluntary and all but intelligent responsiveness of the guitar--its strangely scintillating strings--the so suddenly glorified head of Isabel; altogether, these things seemed not at the time entirely produced by customary or natural causes. To Pierre's dilated senses Isabel seemed to swim in an electric fluid; the vivid buckler of her brow seemed as a magnetic plate. Now first this night was Pierre made aware of what, in the superstitiousness of his rapt enthusiasm, he could not help believing was an extraordinary physical magnetism in Isabel. And--as it were derived from this marvelous quality thus imputed to her--he now first became vaguely sensible of a certain still more marvelous power in the girl over himself and his most interior thoughts and motions;--a power so hovering upon the confines of the invisible world, that it seemed more inclined that way than this;--a power which not only seemed irresistibly to draw him toward Isabel, but to draw him away from another quarter--wantonly as it were, and yet quite ignorantly and unintendingly; and, besides, without respect apparently to any thing ulterior, and yet again, only under cover of drawing him to her. For over all these things, and interfusing itself with the sparkling electricity in which she seemed to swim, was an ever-creeping and condensing haze of ambiguities. Often, in after-times with her, did he recall this first magnetic night, and would seem to see that she then had bound him to her by an extraordinary atmospheric spell--both physical and spiritual--which henceforth it had become impossible for him to break, but whose full potency he never recognized till long after he had become habituated to its sway. This spell seemed one with that Pantheistic master-spell, which eternally locks in mystery and in muteness the universal subject world, and the physical electricalness of Isabel seemed reciprocal with the heat-lightnings and the ground-lightnings nigh to which it had first become revealed to Pierre. She seemed molded from fire and air, and vivified at some Voltaic pile of August thunder-clouds heaped against the sunset.