10 The Martellus forgeries

Bartholomew Columbus (Christopher’s brother) stole the intellectual property of the Portuguese government – being a world map. He traced this world map then made false additions intended to mislead Christopher Columbus backers, (the Catholic Monarchs of Spain and the bank of St George Genoa), into thinking that the route eastwards to China was virtually impossible and that the route westwards via the Americas was significantly shorter and easier.

This deception which was discovered by Professor Arthur Davies when he held the Reardon Smith Chair of Geography at the University of Exeter (1948-1971; reported in Geographical Journal vol 143; p 451) is summarised in the book ‘1421 ch18.

Bartholomew Columbus:

i)   Extended to the tip of South Africa to 45 degrees S knowing the true latitude was 34’ 22’ s (Dias).
ii)  Extended the distance eastwards from Lisbon to China from Approx 116 degrees (Catalan Atlas) or approx 120 degrees (di Virga) to some 230 degrees. i.e. Bartholomew added some 100 degrees distance.
iii)  Inserted a fictitious ‘dog leg’ – a continent south of modern Singapore.

When making these forgeries Bartholomew Columbus was aware of the true shape of the world from Portugal to China through Albertin di Virga’s chart and the true latitude of the ‘Cape of Good Hope’ as he was present when Dias presented his findings to king John of Portugal.