Final answer:
The governess admitting that she has been "carried away" in Harley Street indicates that she has been overcome by emotions or romantic fantasies to a degree that may suggest a lapse in judgment or social impropriety.
Step-by-step explanation:
The governess's admission of being "carried away" in Harley Street suggests that she has allowed herself to be swept up by her emotions or romantic notions, perhaps beyond what is considered socially acceptable or wise.
This phrase often implies a lapse in judgment, where a person gets involved in a situation with an intensity that might cloud their decision-making. In many instances, especially within a Victorian context, a woman being "carried away" might denote that she has been overcome by sentiments which are not typically expressed outright in polite society, which could relate to a burgeoning romance or an imprudent attachment.