The library holds two manuscripts this atlas tracks, and each is missing the same thing: a record of where it was before it arrived.
The Codex Vaticanus, shelfmark Vat.gr.1209, is a mid-fourth-century Greek Bible and one of the two oldest substantially complete ones. It appears in the first surviving catalogue of the library, drawn up in 1475, and nothing certain is known of it before that. How it reached Rome, and from where, is a question the manuscript does not answer. Its modern history is better documented and less comfortable. Napoleon had it taken to Paris in 1809 and it came back in 1815. Through most of the nineteenth century the library allowed scholars only brief and supervised access, which produced a long public quarrel about whether the text was being withheld, and Constantin von Tischendorf was expelled in 1866 for copying more than he had been permitted. A photographic facsimile appeared in 1889 and 1890, and the manuscript has been fully published and digitised since.
The Codex Borgia, shelfmark Borg.mess.1, is a pre-conquest Central Mexican divinatory manuscript, and its silence is longer. It surfaces in the eighteenth century in the collection of Cardinal Stefano Borgia, whose name it now carries, and passed on his death in 1804 to the Propaganda Fide and from there to this library in 1807. How it left Mexico, when, and in whose hands, is not recorded anywhere. Even its place of origin is inferred from its style. The library can say what has been done with the book since 1807 and nothing at all about the three centuries before.