Sentence:  Now one day of the days,...the Sultan cast his eyes upon her as she stood before him, and said to his Grand Wazir, "This be the very woman whereof I spake to thee yesterday, so do thou <WSD>straightway</WSD> bring her before me, that I may see what be her suit and fulfil her need." 
Meaning of the word marked with <WSD> tags:  At once; forthwith.