In Tom's Midnight Garden by Philippa Pearce there's a grandfather clock that strikes thirteen in the middle of the night. Tom discovers time does strange things at that hour.
Below is Philippa's own grandfather clock decorated by Anthony Maitland with images from her book:
On my kitchen wall there are three clocks. It feels as if time is moving about when I look at them -but in a more mundane way. There will be many grannies with families overseas who have clocks like mine, helping them avoid waking people up in the middle of the night.
Time present and time past
Are both perhaps present in time future,
And time future contained in time past.
T.S. Eliot: Four Quartets, Burnt Norton