Sentence:  With the aid of ‘George', the disembodied spirit of an executed felon, Wharton and Wildman looked for treasure at Somerset House, exorcised four devils (Wildman heard one of them ‘hiss'), and embarked on a quest for the <WSD>Urim and Thummim</WSD> from the breastplate of the high priest of the Temple (Wildman calculated that the jewels alone would be worth £25,000). 
Meaning of the word marked with <WSD> tags:  Certain sacred objects (whose precise form and nature is unknown) that were worn on the breastplate of the Jewish high priest, as described in the Bible, and used in divination or casting lots. (from 16th c.)