Ephemerides of Regiomontanus.
Once in Portugal, Columbus was brought in close contact with that eager spirit of exploration which had survived the example of Prince Henry and his navigators. If Las Casas was well informed, these Portuguese discoveries were not without great influence upon the Genoese's receptive mind. He was now where he could hear the fresh stories of their extending acquaintance with the African coast. His wife's sister, by the accepted accounts, had married Pedro Correa, a navigator not without fame in those days, and a companion in maritime inquiry upon whom Columbus could naturally depend,—unless, as Harrisse decides, he was no navigator at all. Columbus was also at hand to observe the growing skill in the arts of navigation which gave the Portuguese their preëminence. He had not been long in Lisbon when Regiomontanus gave a new power in astronomical calculations of positions at sea by publishing his Ephemerides, for the interval from 1475 to 1506, upon which Columbus was yet to depend in his eventful voyage.
Martin Behaim.
The most famous of the pupils of this German mathematician was himself in Lisbon during the years of Columbus's sojourn. We have no distinct evidence that Martin Behaim, a Nuremberger, passed any courtesies with the Genoese adventurer, but it is not improbable that he did. His position was one that would attract Columbus, who might never have been sought by Behaim. The Nuremberger's standing was, indeed, such as to gain the attention of the Court, and he was thought not unworthy to be joined with the two royal physicians, Roderigo and Josef, on a commission to improve the astrolabe. Their perfected results mark an epoch in the art of seamanship in that age.
SAMPLES OF THE TABLES OF REGIOMONTANUS, 1474-1506.
THE AFRICAN COAST, 1478.
[From Nordenskiöld's Facsimile Atlas.]