# The date on the object dates one layer of it > Seven dated objects in this archive show that a date belongs to one layer of the thing: the parchment, the copying, the printing, the compilation. The record has to say which layer, because the other layers carry their own dates and sometimes their own centuries. > The Study - 2026-09-11 > Canonical HTML: https://iconotheca.com/study/the-date-on-the-object-dates-one-layer-of-it/ ## Key points - Seven dated objects in this archive each carry a date that belongs to one physical or textual layer: the animal's death, the copying, the printing, the compilation or the annotation. In no case does that date cover the whole object. - The Tabula Peutingeriana is dated about 1200 by the library that holds it, and the map it copies is dated anywhere from Augustus to about 435 by scholars who disagree in print. Both dates are correct about different layers. - A laboratory date is the narrowest of all. The Voynich radiocarbon result of 1404 to 1438 dates the calves whose skins became the parchment, and the University of Arizona said so; it does not date the ink, the text or the drawings. - Where an object carries no date, three scholars can supply three, as they have for the Selden map: about 1608, about 1619, the 1620s. A date_made field that holds one number without the layer and the dissent is a compression that reads as a fact. ## Seven objects here carry a date, and in each case it belongs to one layer ## The Peutinger map: the parchment is about 1200, the roads are centuries older ## The Mainz Psalter's colophon dates the printing to the day, and nothing else ## Piri Reis dated his own sheet and named the twenty maps it was copied from ## The Voynich radiocarbon date is a date for the calves ## The Genoese map says 1457, and its Asia is from 1444 and its frame from the second century ## The Behaim globe: the accounts date the making 1490 to 1494, the geography stops in 1488 ## The Selden map has no date, so three scholars supply three ## How we write a date in this archive ## Why this archive is free to read A date is a fact about a layer, and an object is a stack of layers with a stack of dates. The seven here carry a colophon precise to the day, a laboratory result precise to the calf, a council account, a maker's own month, and in one case nothing at all with three scholars filling the gap. Write the layer beside the date, list the dissent, and leave the later dates to their own events, because the number that looks settled is the one that gets believed about the wrong layer. ## Questions **How old is the Tabula Peutingeriana?** The parchment scroll in Vienna is a copy made about 1200, according to the Austrian National Library, with a minority hypothesis of 1265 at Colmar. The Roman road map it copies is of disputed date, with proposals in print running from an Augustan survey revised in the fourth or fifth century to a base revised as late as about 435. **What does the Voynich manuscript's radiocarbon date actually date?** The calfskin parchment. Four samples from folios 8, 26, 47 and 68 were dated by the University of Arizona in 2009 to 1404 to 1438 at 95 percent probability, which gives the time the animals died. The ink, text and drawings are presumed to be close in date because vellum was normally used within a few years, but they are not measured. **When was the Selden map made?** Nobody knows exactly, because the map carries no date. Internal evidence puts it between 1607 and 1624. Timothy Brook argues for about 1608, Robert Batchelor for about 1619, and the Bodleian Library's conservation page says the 1620s. The Latin annotations in the margins were added in 1687. **Did Columbus use the Behaim globe?** No. The sphere was finished in Nuremberg in the winter of 1492, after Columbus had sailed in August, and it was still being painted and lettered in 1493 and 1494. Its geography stops with Dias's rounding of the Cape in 1488 and shows no Americas. The two men shared sources, Ptolemy and Marco Polo, not an object. ## Sources - [1] Michael Rathmann, 'Die Tabula Peutingeriana', Osterreichische Nationalbibliothek blog, 21 November 2018. Read in the in-app browser. Source for the copy date of about 1200, the eleven sheets, the dimensions and the acquisition history to 1738. - [2] Renate Burri, review of Richard J. A. Talbert, Rome's World: The Peutinger Map Reconsidered, Bryn Mawr Classical Review 2012.04.14, for the single-hand, layer-by-layer copying and the south German or Alsatian attribution. - [3] Iconotheca, record for the Mainz Psalter, Royal Collection RCIN 1071478, with the colophon text and translation and the record of the hand-added notation and the 1800 presentation. - [4] Republic of Turkey, nomination form for the Piri Reis World Map to the UNESCO Memory of the World Register, 2016, PDF, for the date Muharrem 919, the dimensions, the shelfmark Revan 1633 and the 1929 identification. - [5] Wikisource, 'Piri Reis' Map', translated inscriptions and colophon, for the list of source maps and the Colombo map. - [6] Rene Zandbergen, voynich.nu, 'Radio-carbon dating of the Voynich MS'. Read in the in-app browser. Source for the 1404 to 1438 range at 95 percent, the University of Arizona, the press conference of 8 December 2009 and the statement that the result dates the animal's death. - [7] Beinecke Rare Book and Manuscript Library, Yale University, catalogue description of Beinecke MS 408, for the collation, folio count and materials. - [8] Encyclopaedia of Portuguese Expansion, CHAM, Universidade Nova de Lisboa, 'Genoese World Map drawn 1457', for the dimensions, shelfmark, sources and the translated marginal inscription. - [9] Wikimedia Commons, file description and Library of Congress note for the 1912 Stevenson facsimile plate of the Genoese world map, LOC 97690053, used as the in-body plate and identified as a facsimile. - [10] Germanisches Nationalmuseum, Objektkatalog, 'Erdglobus, sogenannter Behaim-Globus', WI 1826, for the craftsmen named from the council records, the 1490 to 1494 making, the 1510 ring and the 1937 purchase. - [11] Bodleian Libraries, 'The Selden Map of China conservation project'. Read in the in-app browser. Source for the 1620s dating, the 1659 arrival, the 1687 annotation by Hyde and Shen Fuzong, the retained border and the draft routes found on the verso in 2011. - [12] Robert K. Batchelor, 'The Selden Map Rediscovered: A Chinese Map of East Asian Shipping Routes, c.1619', Imago Mundi 65:1, 2013, for the about-1619 dating and the January 2008 reading.