The dull flip-flop of Lucrecio’s sandals tickles the edge of my consciousness as he shuffles across the tiled floor to heave open the shutters and summon the morning light to invade my slumbers.

"Time to get up, Signor!"

Get up? Did he say get up? Get up assumes some degree of verticality, and vertical is a dimension that’s been singularly lacking in my life of late.

Oh I grant you I do get up the ladder, one hundred and seventeen calf-cramping rungs of it - beware the sixty third which is loose! They’re careless workmen, these Romans; you can’t trust a thing they make.

Can’t even trust the Pope!

I agreed with him that the ceiling needed re-painting. D’Amelia’s starry firmament was incompatible with the structure of the Chapel; but, as I pointed out at the time, I am not a painter. It was the prospect of sculpting the allegorical figures for the papal tomb that enticed me to quit Florence for this God-forsaken city. Only having got me here His Holiness, in a fine display of Christian benevolence, informs me that, if I want to get paid, I’d better get on and paint the ceiling.

"Paid," that’s a joke if you like! More than once I’ve had to down tools and walk out before he’d cough up what he owes. And all the while there’s a whole tribe of Buonarrotis, lounging around the gardens of Florence, looking to me to provide for their every need. Sometimes I think that nobody has more needs than a Buonarroti!

So here I lie crammed in beneath the ceiling twenty metres up in the air roped to a plank with my arm outstretched above me from now until supper time.

The ache starts, as always, after about an hour. A niggling cramp grasps me just below the thumb and gradually radiates tingling tentacles of torture around my wrist, across the back of my hand and along my arm, benumbing my elbow and screwing the muscles of my shoulder into an agonising knot of tension.

I change hands but that is of little use because my left hand lacks the dexterity of my right. Lucrecio tells me I should get the apprentices to do some of the work, filling in the larger areas of colour, but they make so many errors simply mixing the pigments I could never trust them with the actual painting. After all, it’s my reputation that will hang on this ceiling.

I recall the day the scaffolding was removed from the first section and I was able for the first time to study the manifestation of my design, the columns and panels continuing the structural lines of the building to create the impression of a massive arched stone ceiling. It was perfect and I surveyed it with immense satisfaction - until I noticed a fold in a robe that is not quite right.

No I will not tell you which one!

When I was a youngster, learning my art, my master cautioned me always to be aware that each small brush stroke is part of a greater whole. "Stop boy," he would say, "pause, step back and view it from a distance." Not the most helpful advice for this job!

They bring me bread, cheese, a cup of tepid water, for refreshment. Then I resume my labours, consoled today by the knowledge that at last I have begun work on the final panel. Here sits the prophet Jeremiah, a mighty man exhausted, slumped forward, round-shouldered, pensive, bowed down with physical weariness. His callused hands, his ragged beard, his care-worn countenance are mine.

As I work the pain in my shoulder migrates along my spine until my hips and even my knees and ankles start to ache with the strain of my unnatural position. I’ve been up here for more than twelve hours. My body cries out for relief, for food, a warm bath and sleep. Wearily I head for home.

Laughter emanates from my room, the mocking sound of happiness.

Lucrecio welcomes me with excited babble, "News, news, Signor! A visitor from Florence!"

My brother, plump and shiny, rises grinning from my favourite chair, throws wide his soft skinned hands and greets me with the same old joke, "What’s this I hear; you’ve been lying down on the job again, Michaelangelo?"

All the tension in my body rushes to the paint encrusted fingers of my right hand and they clench into a rock hard fist while the pent-up pain and frustration of the last four years take control of my arm.

I’ll give him lying down!