Einstein's Equation

I just received David Bodanis' book, E=mc2 in the mail. I'm not a fan of popular physics books, as I feel that without the mathematical background, important concepts are conveyed by meaningless caricatures. With biology it's different - powerful ideas can be communicated without mathematical language and are accessible to the non-specialist.

However, this book looks great as it focusses on the history of ideas leading up to Einstein's famous 1905 publications. Its a treasure trove of anecdotes and I can't resist copying out a few lines from the introduction. Discussing the difficulty in grasping the meaning of 'Einsteins equation', Bodanis writes:

Even firsthand instruction doesn't always help, as Chaim Weizmann found when he took a long Atlantic crossing with Einstein in 1921: "Einstein explained his theory to me every day," Weizmann said, "and soon I was fully convinced that he understood it."