It’s an undocumented feature of working in a major public library.

The simple pleasure of walking through the library in the hours before opening. You tend to walk lightly and whisper even when the place is deserted. There is something slightly ethereal about wandering around in empty spaces; ones that are typically occupied or at least intended to be: Libraries. Churches. Concert halls. Sports stadiums.

There’s an even stranger feeling in a place that is normally crowded and quiet. Normally seen but not heard. Are they lurking somewhere unseen? The eyes, following.

Even better: roaming around, alone, at 2 o’clock in the morning, waiting for software updates and system upgrades to complete.