One of the oldest earth mysteries was 'what shape is it?' Eratosthenes, in 240 BC, was able to prove the sphericity of the earth and estimate its size to a reasonable margin of error, by comparing the angle of the sun at two distant locations simultaneously. Aristotle knew that the earth was spherical, citing the horizon, the Earth's circular shadow during lunar eclipses, and other phenomena. Many educated people knew about the spherical earth from late antiquity on. However, most Europeans believed that the earth was flat until the explorations of the renaissance.
In the late 19th century a number of alternative theories of the shape of the earth were proposed, flat, hollow and inside-out. By the time the poles had been reached in the early 20th century, the time for these theories had passed. Today, some Biblical inerrantists still believe that the Earth is flat.
This book contains collection of 8 Titles as given below:
1. Symzonia; Voyage of Discovery
2. Journey to the Center of the Earth
3. Etidorhpa
4. The Smoky God
5. The Phantom of the Poles
6. At the Earth's Core
7. Pellucidar
8. A Journey to the Earth's Interior