Snape kept at it for another hour and Hermione left with a splitting headache. By the end of the hour, she had managed to at least block Snape from entering her memories completely. At least for a moment before he viciously tore down her mental barrier and caused her to pass out. It was only then he had relented that they stop for the day and handed her a few potions for her to gather her strength again before he ushered her from his office without another word.