so fell night upon the woods and all was still , and a great dread for niniel fell upon tamar , so that he cursed his weakness and his heart was bitter , yet did he cease not to follow so swiftly as he might , and losing sight of her he bent his course towards that part of the forest nigh to the ravine where had been fought the worm 's last fight , for indeed that might be perceived by the watchers on the hill .