Note 4 — THE LEARDO MAP OF THE WORLD 1452 OR 1453

As much of this digit as remains might be the upper part of either a 2, a 3, or a 7. Since the Easter calendar begins with 1453 the date could hardly be earlier than Easter, 1452. For the same reason, it is not likely to have been as late as 1457, the only possible date after 1453. On the Vicenza Leardo map the Easter calendar begins with the year in which the map is dated, 1448; on the Verona map of 1442 the calendar begins with the preceding year, 1441. A discrepancy of four years between the beginning of the calendar and the date of the map, however, is most improbable.

Santarem, Vol. 3, p. 399, and Berchet, op. cit., p. 6, cite two 22 mid-eighteenth century MSS in the Library of St. Mark’s, Venice, which contain entries relating to a map by Giovanni Leardo dated 1447. One of these MS is that of the Doge Marco Foscarini (Codex ital., XI, 123, p. 42), the other that of a contemporary scholar, Giovanni degli Agostini (Codex ital., VII, 291, p. 542; this and the preceding reference were furnished to the present writer by the Chief Librarian of the Library of St. Mark’s; they do not agree exactly with the references as given by Santarem and Berchet).

The passage from the Foscarini MS (Fig. 2) may be translated thus: “Gio. Leardo, who flourished in 1440, made a planisphere on parchment on which was written Leardius de Venetiis me fecit anno 1447. It was at the house of (era presso) Bernardo Trevisano. Apostolo Zeno saw it many times and marveled at seeing the exactness of the design.” The passage from the Agostini MS (Fig. 3) runs as follows: “Giovanni Leardo: This (man) lived shortly before the middle of the fifteenth century, and he delighted in geography and spheres. In the Trevisan Library was preserved a planisphere by him on parchment on which could be seen delineated the whole terraqueous globe with all the signs and celestial constellations, beneath which, according to his assertion, every part is placed. At the bottom of this parchment these words may be read: Joannes Leardius de Venetiis me fecit ab anno 1447. It is curious to see how in his time, when not many discoveries had been made and navigation was so little advanced, the positions of the provinces and of the seas were conceived.”

Berchet, op. cit., p. 7, points out that the arms at the top of the parchment of the Leardo map now belonging to the American Geographical Society are those of the Trevisan house. He reads incorrectly, however, the date given by Agostini as 1452, concluding therefrom that the map mentioned by the latter was the same as the Society’s map, the date of which he also reads as 1452. In view of the actual difference in the dates, we may conclude that Leardo constructed two maps for the Trevisan family, and that the one dated 1447 is yet to be rediscovered.