About the hour of nine
If he comes again , he shall not go away unknown . '' When the evening came , Matilda was again at her casement . The night was as beautiful as the preceding one ; but there was a thin halo round the moon that gave her a softer aspect ; and the diminished sound of the mellow ripple of the Whitadder seemed to indicate that there was a zephyr abroad whose presence could be detected only by that delicate test . About the hour of nine , she saw the thin figure of old Bertha , rolled up in a cloak , steal silently from a postern of the east wall , and creep slowly down to the end of the light , airy bridge , that spanned , with its pure white arms , the bosom of the river . Stretching forth her bony hand , she seized the rail , and , having got a firm footing , walked with slow steps along the planks . Her progress was slow , nervous , and unsteady . Matilda was solicitous for her safety ; for she had never seen Bertha venture along the bridge at night , and she herself seldom crossed it after nightfall , even with the aid of a resplendent moon .