Comment Re:Why don't they just ... (Score 3, Interesting) 117
I also read about it in Tarzan at the Earths core by Edgar Rice Burroughs. That book describes how the Earth is hollow, with openings to the inhabitable inner world at the north and south poles.
In that book, Jason Gridley decided to build a rigid airship, using helium, with sufficient range to fly through the polar opening to the inner world and back. But, he was unsure how to build a hull that was sufficiently strong and light that could survive the conditions along the way. Not sure how to solve that problem, he traveled to the jungles of Africa to ask Tarzan for his advice. Fortunately, Tarzan had recently heard about a nearby lake-dwelling tribe that was using canoes made of a metal that was as strong as steel and as light as cork.
The book said that inner world had accidentally been discovered previously by David Innes and Abner Perry who had been planning to look for anthracite coal with their newly invented mechanical prospector. But, on their trial voyage, their steering mechanism jammed and they accidentally drilled 500 miles down into the Earth's core, reaching the hollow inner world. Perry remained behind, while Innes made the difficult trip back to the surface. The book does not mention them having any problems with the drilling mechanism becoming too hot.
Jason and Tarzan went on to build their 997 foot long airship from harbenite. Jason knew that Tarzan's skills would prove useful one the reached the Earth's core.