Oct. 6. Frodo reaches Weathertop observed by the Nazgul. Aragorn sees [three Riders] coming back from a patrol of the Road west of Weathertop.
The camp is attacked at night by [five Riders]; but they are driven off by Aragorn; and withdraw after wounding Frodo. [The Witch-king] now knows who is the Bearer, and is greatly puzzled that it should be a small creature, and not Aragorn, who seems to be a great power though apparently 'only a Ranger'. But the Bearer has been marked with the Knife and (he thinks) cannot last more than a day or two.
It is a strange thing that the camp was not watched while darkness lasted of the night Oct. 6-7, and the crossing of the Road into the southward lands seems not to have been observed, so that [the Witch-king] again lost track of the Ring. For this there were probably several reasons, the least to be expected being the most important, namely that [the Witch-king], the great captain, was actually dismayed. He had been shaken by the fire of Gandalf, and began to perceive that the mission on which Sauron had sent him was one of great peril to himself both by the way, and on his return to his Master (if unsuccessful); and he had been doing ill, so far achieving nothing save rousing the power of the Wise and directing them to the Ring. But above all the timid and terrified Bearer had resisted him, had dared to strike at him with an enchanted sword made by his own enemies long ago for his destruction. Narrowly it had missed him. How he had come by it - save in the Barrows of Cardolan. Then he was in some way mightier than the B[arrow]-wight; and he called on Elbereth, a name of terror to the Nazgul. He was then in league with the High Elves of the Havens.
Escaping a wound that would have been as deadly to him as the Mordor-knife to Frodo (as was proved at the end), he withdrew and hid for a while, out of doubt and fear both of Aragorn and especially of Frodo. But fear of Sauron, and the forces of Sauron's will was the stronger.
Oct. 7. He arose and cried out to his companions, and drew [the other four] back to him. He then patrols the Road to the Bridge of Mitheithel, knowing that it was practically impossible to cross the Grey-flood between Tharbad and the Bridge (while [the four Riders who pursued Gandalf] are away north along the upper river). The Nazgul search in vain for the Bearer while Aragorn leads Frodo in the pathless lands south of the Road.