A sphere made from two ostrich eggs fused together may be the world's oldest globe to include the New World, Discover magazine reports, the rare, grapefruit-sized globe depicting North America found last year at a London map fair by an anonymous collector.
According to a new analysis by independent Belgian scholar, Stefaan Missinne, the ostrich egg globe predates the previous record holder for world's oldest New World globe, made of copper alloy sometime between 1504 and 1506. The copper globe is on display at the New York Public Library, but according to Discover, new evidence suggests that the recently discovered ostrich egg globe was used as a reference point to create it.
The northern and southern hemispheres of the ostrich egg globe came from the bottom half of an ostrich egg, and to determine its age, Missinne sent it to a radiologist, who used CT scans to measure the bone density loss of the shell. The loss was then compared to the density of modern ostrich eggs and eggs of "known ages in museum collections." Missinne was able to calculate that an ostrich egg loses its bone density about 10 percent each century, meaning that the ostrich egg globe is likely from the year 1500.
It makes sense that the first "New World" globe (or at least the first one scientists have discovered) would be engraved on an egg before being used as a model for the copper version, as copper can be melted and egg cannot. Missinne describes in the Washington Map Society journal, the Portolan, how she suspects an Italian engraved the ostrich egg globe, as in 1500, Florence was the richest city in Europe and a hub for map-makers, where wealthy and powerful families funded exotic cultural and artistic projects.
While Leonardo Da Vinci was certainly a "creative force" in Florence at the time, Missinne dismisses the idea that he could have made the ostrich egg globe, as his writing lacked New World references. However, Da Vinci's method of transferring paper map to globe is evident by the way its maker appears to have sliced 2D drawings into 3D triangles. At the time the ostrich egg globe was created, explorers were returning from their journeys to North America, reflected in the globe's shape of shape of the Asian peninsula.
