Retire to bed shortly after midnight.

At 1am, my over-stimulated mind is still wide awake, straining to pick up the pattern of late-night footsteps and stray bits of conversation outside.

At 2am, nothing moving save the odd car.

At 3am, black silence, broken only by the quarterly chiming of the church bells solemnly charting the progress of my insomnia. I feel suffocated by the circularity of my thoughts in the darkness.

At 4am sharp, entry of the dawn chorus.

The birds’ joyous polyphony is strangely soothing, and I shift my focus to the individual song-lines, registering sounds unfamiliar to the Londoner’s ear. Slowly, dozily, fuzzy sleep arrives.

Cheery morning is there all too soon, announced by those unforgiving chiming bells.