Let me add a word or two about that quaint Baron Vordenburg, to whose curious lore we were indebted for the discovery of the Countess Mircalla’s grave.
He had taken up his abode in Gratz, where, living upon a mere pittance, which was all that remained to him of the once princely estates of his family, in Upper Styria, he devoted himself to the minute and laborious investigation of the marvellously authenticated tradition of Vampirism.
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How they escape from their graves and return to them for certain hours every day, without displacing the clay or leaving any trace of disturbance in the state of the coffin or the cerements, has always been admitted to be utterly inexplicable. The amphibious existence of the vampire is sustained by daily renewed slumber in the grave. Its horrible lust for living blood supplies the vigour of its waking existence. The vampire is prone to be fascinated with an engrossing vehemence, resembling the passion of love, by particular persons. In pursuit of these it will exercise inexhaustible patience and stratagem, for access to a particular object may be obstructed in a hundred ways. It will never desist until it has satiated its passion, and drained the very life of its coveted victim. But it will, in these cases, husband and protract its murderous enjoyment with the refinement of an epicure, and heighten it by the gradual approaches of an artful courtship. In these cases it seems to yearn for something like sympathy and consent. In ordinary ones it goes direct to its object, overpowers with violence, and strangles and exhausts often at a single feast.
Harenberg's 1733 book was published in German (see the accompanying illustration), but somehow got a Latin title in Calmet's book, and this must be the reason why Le Fanu uses a Latin title and spells Harenberg's name 'Herenberg' like Calmet did. Phlegon's De Mirabilius will be well-known to readers of books on vampires, and Augustin's De cura pro mortuis gerenda is a key Catholic text on the care for the dead.
Regular visitors of this blog probably would like to have at their fingers' ends all these and other books on the subject.