As with the system of bells aboard ship, or the solemn order of prayer services in a monastery, the day at Unseen University appears to be regulated by its mealtimes, which rather like the Bells aboard a ship, seem to occur at two-hourly intervals throughout the day and night.
Second Breakfast happens at eight o'clock in the morning. It follows on from Early Breakfast at six o'clock, and is likely to be succeeded in normal circumstances by some sort of mid-morning snack, maybe even an early elevenses, at ten o'clock. In fact, coffee, tea, and biscuits (and by inference in the text of Unseen Academicals, a selection of cakes) are circulated on a specially reinforced heavy-duty tea-trolley at eleven-thirty in the morning, a fact of supreme importance to wizards engaged in endless or pointless Faculty meetings. The text of Unseen Academicals also suggests the previous meal is over and done with by nine, leaving an unprecedented two and an half hour gulf before the tea trolley appears. This left an inexplicable gap which was filled then by third breakfast, discovered by Archancellor Flacker whose statue stands in the UU grounds and was used as a goal post in Unseen Academicals.