The Foyle copy of the Mirabilia Romae..., a combined devotional text and practical guide for pilgrims to Rome, dated to around 1475, lacked 44 of the 92 xylographic leaves, but this is a much, much rarer text than that found in such blockbooks as the Biblia Pauperum or the Speculum humanae salvationis, and only six other copies are recorded. Just four of them are complete, including those held in the British Library and the John Rylands Library, but like the copy in a contemporary pigskin binding, and containing the original pilgrim’s annotations, that was last cited in an American collection in 1962, scholars had rather lost track of the location of the Foyle copy since it was last sold at auction – at Sotheby’s in 1931.
The Historia et Descriptio urbis Romae, as it is more properly known, combines two texts. The Mirabilia is concerned with the wonders of Rome, while the Historia..., as the longer title indicates, provides a history and guide to the Eternal City for pilgrims, but its ultimate aim was devotional, in that it guided pilgrims in their worship. A German translation had existed as early as the 14th century, and it is this text, probably the earliest in printed form, that is used.
It is also unusual among blockbooks in containing few illustrations and extensive text, and is further distinguished by being opistographic, that is to say, printed on both sides of the paper and on a printing press (possibly that of Ulrich Han in Rome), whereas blockbooks were more commonly printed on one side of the sheet only, and by rubbing the sheet against the inked block.In an early 20th century binding of gilt panelled purple-brown morocco, signed W. Pratt, William Foyle’s incomplete copy had the missing leaves supplied from a lithographic facsimile produced by Berjeau in 1864 (which itself was limited to just a dozen copies) but though the price was just £18 when it it last appeared at auction, almost 70 years ago, the bidding this time reached £110,000 before this rare blockbook was knocked down to H.P. Kraus.