A SCIENTIFIC discovery is the outcome of an interesting 

 process of evolution in the mind of its author. When we are 

 able to detect the germs of thought in which such a discovery 

 has originated, and to trace the successive stages of the rea- 

 soning by which the crude idea has developed into an epoch- 

 making book, we have the materials for reconstructing an 

 important chapter of scientific history. PROF. J. W. JUDD, 

 Critical Introduction to Bettany's Edition of Darwin's "Structure 

 and Distribution of Coral Reefs" 



