Sometimes there was fair degree of chance, such as Fleming's discovery of penicillin. Likewise Joseph Priestley was apparently was just curious about what would happen if he heated mercuric oxide, and so discovered oxygen. Often however, it was more a case of years of struggle rather that instant insight. Darwin held off publication of the theory of evolution for many years. Wegener didn't have his ideas of continental drift accepted in his lifetime. And Einstein struggled for years with the ideas of General Relativity. The final two chapters describe the DNA story of Watson and Crick and the work of Benoit Mandelbrot on Fractals.