ONE day in the year 1896, a French chemist named Becquerel took a photographic plate, which had been wrapped in light- proof paper, from one of the drawers of his laboratory. When it was developed, it showed dark smudges for which he could find no immediate explanation. His curiosity was aroused, and he did not rest until it was satisfied. The result of his inquisitiveness was the discovery of radium.1
Historians, in developing the story of Lincoln's assassination, have encountered smudges equally baffling. Why did General Grant suddenly alter his plans and decide not to go to Ford's Theater on the evening of Lincoln's assassination? Who, during that same night, tampered with the telegraph wires leading out of Washington? Why was the President's bodyguard at the playhouse, guilty of the grossest negligence, not punished nor even questioned?
Perhaps the most serious reproach against historical writers is not that they have left such questions unanswered, but that they have failed to ask them.____________________