Whatever was "An Ordinary" that you could have at the New Brighton Hotel on Sundays during the summer?
Only just saw this post today and I wondered the same thing.
According to dictionary.com:
14. British (in a restaurant or inn), a complete meal in which all courses are included at one fixed price, as opposed to ŗ la carte service.
15. a restaurant, public house, or dining room serving all guests and customers the same standard meal or fare.