If one looks about him in the scientific world for the most striking characteristic of our times, he will find it, perhaps, in the systematic organization of investigative work. There has never before been a time when original research has been so carefully planned or so consciously directed as now. The world is tremendously impressed with the results of science attained during the last two centuries, but it would not be surprising, with the immense system of inquiry now in vogue, if during the twentieth century discoveries were made which would exceed in number and eclipse in grandeur those of all the centuries which have preceded.
In the forward march of science, great theories are originated, have their day and are demolished. But it is surprising how often an old theory, thought to be thoroughly extinct, will be exhumed and resuscitated. Like Colonel Bogy of the golf links, a scientific