Why this horror, that caused Shelley to drop the pen, at this recollection of a common-place bit of landscape, justly styled 'a tame and uninteresting assemblage of objects,' beheld by him for the first time just five years ago;--no, not this horror _at_ the recollection of so tame a scene, but this horror _at_ recollecting how often the uninteresting scene had recurred to him in his dreams? Those who would know the Real Shelley, whose long locks, peculiar dress, and eccentric aspect, were matters of tattle and laughter in the common-rooms of the colleges in 1810-11, should ponder this self-revelation of Shelley's own soul, and should also take heed of his widow's note upon it. Let readers recall what they have been told of the way in which Byron's memory, sensibility, and imagination acted and inter-acted upon one another; the memory stirring the sensibility, the sensibility quickening the imagination, the imagination stimulating the memory again and again, till the recollections of old impressions far surpassed the original impressions in vividness and intensity; and let them then observe how Shelley was similarly constituted, with a memory singularly retentive of particular impressions, a sensibility (apt to be roused to morbid activity by these recollected impressions), and an imagination no less quick at the instance of sensibility to intensify the pictures of memory. It was thus that the tame scene, so clearly and deeply printed in his mind as to be repeatedly offered by memory to his re-awakening consciousness, acquired a vividness that was in itself terrifying. But the terror begotten of this vividness was not the terror that made the poet drop his pen. Whilst his sensibility was being stirred to morbid and distressing activity by recollection and fancy, he was suddenly surprised by remembering how repeatedly the same tame scene had come back to him in dreams,--_i.e._ at the moment of the re-awakening of consciousness,--and in his agitation, heightened by perplexity at so singular a fact, the surprise affected him with horror, even as any surprise (one that is the merest trifle to a cool and self-possessed mind)--a surprise arising from the rustling of a leaf, the echo of a footfall, the shadow of a spray by moonlight,--is apt to plunge the agitated and unbalanced mind into the Horror of Perplexity.