Italian Paleography


Chicago, Newberry VAULT slipcase Ayer MS map 1
Gregorio Dati
The Sphere
Italy, around 1425

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_La Sfera _is a pedagogical text composed in rhyme designed to instruct students in the astronomic and geographic sciences.  The work is divided into four books, concerning, in succession: cosmography and astrology; climates and the seasons; the use of the compass and navigational instruments; and a geographical survey of the southern shores of the Mediterranean Sea from Gibraltar to the Levant.  Marginal illuminations throughout the first three books explain phenomena such as lunar and solar eclipses, climatic zones, and the structure of the cosmos. The final book is illustrated by maps, partially based on the common navigational charts of the day, known as portolan charts to modern scholars.  Curiously, these maps cover only the southern shore of the Mediterranean Sea from the Straits of Gibraltar to the Levant, and there is some debate about whether its author, likely Gregorio Dati, intended to include a fifth book covering the northern shore of the Mediterranean, including Italy.  Dati was a Florentine merchant who rose from humble beginnings to become a prominent member of the ruling city council.

The maps would not have been useful for actual travel, but surely would have helped readers make an imaginary pilgrimage or put events of ancient and Biblical history in their geographical context.  While not an exhaustive treatment of its subject, La Sfera did provide a summary of important geographical and celestial information any Florentine merchant would need to know.  That it filled this need well is attested in the survival of more than 200 manuscripts in European and American libraries, an unusually large amount given the inevitable abuse and attrition of didactic texts.

Folios 12v and 13r featured on the site represent the zodiac and cosmos, and describe the worldview of the quattrocento, poetically describing the winds.  The pages of the manuscript glow thanks to use of gold leaf and ultramarine blue in the illuminations.


Umanistica posata, regolare, dal tracciato sottile e forme rotondeggianti.
Da notare: la a con tratto superiore richiuso (2v, r. 1: gran); la g di tipo ‘poggiano’ costituita da due occhielli tondi uniti da un tratto verticale mediano (2v, r. 16: giermani); la e tra due barre oblique a indicare la copula (13r, r. 23: è); la decorazione dell’iniziale S tipicamente umanistica coiddetta ‘a bianchi girari’.

Selected Bibliography:

Item fully digitized here.