That was something he had not thought of, before. It gave him an ugly start. He was still thinking about it as he turned into the side hall to the History Department offices and entered the cubicle he shared with a colleague. The colleague, old Pottgeiter, Medieval History, was emerging in a rush; short, rotund, gray-bearded, his arms full of books and papers, oblivious, as usual, to anything that had happened since the Battle of Bosworth or the Fall of Constantinople. Chalmers stepped quickly out of his way and entered behind him. Marjorie Fenner, the secretary they also shared, was tidying up the old man's desk. "Good morning, Doctor Chalmers." She looked at him keenly for a moment. "They give you a bad time again in Modern Four?" Good Lord, did he show it that plainly? In any case, it was no use trying to kid Marjorie. She'd hear the whole story before the end of the day. "Gave myself a bad time." Marjorie, still fussing with Pottgeiter's desk, was about to say something in reply. Instead, she exclaimed in exasperation. "Ohhh! That man! He's forgotten his notes again!" She gathered some papers from Pottgeiter's desk, rushing across the room and out the door with them. For a while, he sat motionless, the books and notes for General European History II untouched in front of him. This was going to raise hell. It hadn't been the first slip he'd made, either; that thought kept recurring to him. There had been the time when he had alluded to the colonies on Mars and Venus. There had been the time he'd mentioned the secession of Canada from the British Commonwealth, and the time he'd called the U. N. the Terran Federation. And the time he'd tried to get a copy of Franchard's _Rise and Decline of the System States_, which wouldn't be published until the Twenty-eighth Century, out of the college library. None of those had drawn much comment, beyond a few student jokes about the history professor who lived in the future instead of the past. Now, however, they'd all be remembered, raked up, exaggerated, and added to what had happened this morning. He sighed and sat down at Marjorie's typewriter and began transcribing his notes. Assassination of Khalid ib'n Hussein, the pro-Western leader of the newly formed Islamic Caliphate; period of anarchy in the Middle East; interfactional power-struggles; Turkish intervention. He wondered how long that would last; Khalid's son, Tallal ib'n Khalid, was at school in England when his father was--would be--killed. He would return, and eventually take his father's place, in time to bring the Caliphate into the Terran Federation when the general war came. There were some notes on that already; the war would result from an attempt by the Indian Communists to seize East Pakistan. The trouble was that he so seldom "remembered" an exact date. His "memory" of the year of Khalid's assassination was an exception.