Although Einstein is widely credited with abolishing the ether concept, he actually introduced a new relativistic ether in 1916, developing the idea in his later works. This book relates the story of Einstein and the rebirth of the ether, demonstrating how Einstein came to reject the 19th century ether. It details three relativistic ether models developed by Einstein and Einstein's treatment of spacetime as a material entity-a "new ether"
This book references most all of the papers and correspondences Einstein wrote over the lifespan of his theories, in special regard to how his feeling about the Ether changed. Very well written, Ideally referenced, and not a crackpot book at all!