midnight
`` Banish all thoughts of her from your breast . You will never behold her again . I will give you time for reflection on my proposal . An hour before midnight I shall return , and if I find you in the same mind , I abandon you to your fate . '' And with these words he stepped back towards the lower end of the cell . Wyat instantly sprang after him , but before he could reach him a flash of fire caused him to recoil , and to his horror and amazement , he beheld the rock open , and yield a passage to the retreating figure . When the sulphureous smoke , with which the little cell was filled , had in some degree cleared off , Wyat examined the sides of the rock , but could not find the slightest trace of a secret outlet , and therefore concluded that the disappearance of the demon had been effected by magic .