I'VE BEEN ORDERED TO THE PEOPLE'S REPUBLIC OF BANANA to count fish. I'm looking forward it. I should have done it 20 years ago, when London University invited me to Belize. Live in a hut, dive twice a day, write down how many blennies you see, lie in the sun, drink rum. Free.
The missus had graciously consented to the Belize trip on the condition that I underwent a full medical. Wilmshurst was Head of Thoracic Medicine at St Thomas' and Chief Medical Officer of the BSAC. He was happy to oblige. Suspiciously happy, in fact.
I was fit then. I'd run the London Marathon and was drinking only three times the recommended weekly intake of alcohol for a corpse.
Wilmshurst examined me. "You'll do," he conceded. "Since you're here, would you be a control in an experiment I'm conducting?"
He had this theory. A PFO is a leaky heart valve of which you could be blissfully ignorant until you died peacefully in your sleep, aged 110. But put it under pressure, and tiny bubbles could provide seeds for vagrant nitrogen and mutate into big, bend-inducing bubbles.
He dripped saline solution into my arm and studied its progress through my heart with a dinky little scanner thing. Which he then hurled to the floor in a rage. "Well! That was a bloody waste of time! You've got one!''
"Got one what?"
"A PFO. Now I'm going to have to find some other bugger to be my control." I stood there helplessly in my underpants while he wrenched the equipment apart. He tore the sensors off my chest, ripping out clumps of my body hair. "Don't dive. Goodbye."
Twelve miserable, dry, months crawled by. Wilmshurst was taking an age to analyse his findings. If divEr hadn't called, I may have run amok with an axe. They wanted to know if I'd like to go to Gozo.
The dive guide picked me up from my hotel in his shagged-out Land Rover and we rattled along rutted goat tracks to the coast. We paddled along the shore to the rim of a blue hole.
"This,"Ari explained unnecessarily, "is the Blue Hole."
"And would it be more than nine metres deep?" I enquired.
"No," he replied. I smiled. "Good."
"We leave the Hole at nine metres, then we go down to 46 metres. There, I show you the Cave of the Angels."
Then splosh, he was gone. Maybe I should've mentioned the PFO, but it was too late now. With a mental shrug, I slipped into the Blue Hole and sank like a stone. Ari motioned me to be careful (ha!) and slipped through a fissure into the darkness.
I've never liked caves. I followed with a heavy, perforated heart. Then I almost choked. Above me soared a vaulted cathedral ceiling, draped with gleaming, ice-white curtains of coral. It was as intricate as lace and more delicate: the bubbles from our exhausts swayed upwards like silver Frisbees and knocked the coral from the roof. It tumbled down in slow motion, fragments of a mermaid's veil.
Horrified, I tugged at Ari's fin and jabbed my finger at the cave entrance. He seemed puzzled, but he finned towards the door.
I accosted him at the surface. 'Those corals took thousands of years to grow and we've destroyed them in five minutes! It's submarine vandalism!''
"So?" he replied amiably. "If we don't seen them, they are in the cave for another thousands of years with no persons to love them."
I was so busy considering the philosophical ramifications of Ari's argument, I quite forgot to notice that I was still alive.