The singularity of the narrative seems to me to be this, that it describes the ghost of a hand, and no more.

The person to whom that hand belonged never once appeared: nor was it a hand separated from a body, but only a hand so manifested and introduced that its owner was always, by some crafty accident, hidden from view.
In the year 1819, at a college breakfast, I met a Mr.Prosser--a thin, grave, but rather chatty old gentleman, with very white hair drawn back into a pigtail--and he told us all, with a concise particularity, a story of his cousin, James Prosser, who, when an infant, had slept for some time in what his mother said was a haunted nursery in an old house near Chapelizod, and who, whenever he was ill, over-fatigued, or in anywise feverish, suffered all through his life as he had done from a time he could scarce remember, from a vision of a certain gentleman, fat and pale, every curl of whose wig, every button and fold of whose laced clothes, and every feature and line of whose sensual, benignant, and unwholesome face, was as minutely engraven upon his memory as the dress and lineaments of his own grandfather's portrait, which hung before him every day at breakfast, dinner, and supper.
Mr.Prosser mentioned this as an instance of a curiously monotonous, individualised, and persistent nightmare, and hinted the extreme horror and anxiety with which his cousin, of whom he spoke in the past tense as 'poor Jemmie,' was at any time induced to mention it.
I hope the reader will pardon me for loitering so long in the Tiled House, but this sort of lore has always had a charm for me; and people, you know, especially old people, will talk of what most interests themselves, too often forgetting that others may have had more than enough of it..