this from Pierce Egan’s “Walks Through Bath...,”(1819)

An excellent band of music, during the season, plays from one to half-past three o’clock every day, in this elegant and spacious room,( the PumpRoom-JW) which is open from an early hour in the morning till four in the afternoon; and, during the time of performance of the band, the room is well filled with company. The remuneration for drinking the water here is left entirely to the liberality of the visitor; no specific demand being made. To those persons who are fond of bustle and gaiety, this promenade in the Pump-Room will be found highly attractive. In no place in Bath does an hour pass away more agreeably.

These were the fashionable hours- from one o'clock to three p.m., when the room would have been at its most crowded with fashonable people,as Catherine disocevered in Cahpter4

With more than usual eagerness did Catherine hasten to the pump–room the next day, secure within herself of seeing Mr. Tilney there before the morning were over, and ready to meet him with a smile; but no smile was demanded — Mr. Tilney did not appear. Every creature in Bath, except himself, was to be seen in the room at different periods of the fashionable hours; crowds of people were every moment passing in and out, up the steps and down; people whom nobody cared about, and nobody wanted to see; and he only was absent. “What a delightful place Bath is,” said Mrs. Allen as they sat down near the great clock, after parading the room till they were tired; “and how pleasant it would be if we had any acquaintance here.”