Being a natural wimp, I couldn't believe it either as I stood in the sun, knees buckling under the weight of the tank, ready to follow Sue in a free-fall to the water's surface.
"Fix your eyes on the horizon," said Garvin, our Bahamian divemaster. "OK, now step forward." My brain tried to tell my leg to move but the leg wasn't keen. "Go on," said Garvin. "You'll be fine." So I stepped, and after a moment's confusion and noise, the turquoise world below became a place of deep calm and quiet. Except for the sound of breathing. In... out... in... out. We had been warned: if you hold your breath while swimming upwards, the pressure change expands the air; your lungs explode and you die.
I'd had no intention of diving when I arrived three days earlier at Small Hope Bay Lodge on Andros island, in the Bahamas. I'd booked in for a winter getaway - a week's yoga course - but everyone, including Dolly, the yoga instructor's mother-in-law, who is in her seventies, was snorkelling or diving between classes. It seemed a shame to miss out.
Sue and I did our safety training one afternoon. Garvin took us out to Goat Cay, a tiny island with a shelving white-sand beach. He was thorough, repeating the procedures until we had them right - how to breathe underwater, how to hold our noses and blow to equalise ear pressure, and how to replace mask and mouthpiece should they get knocked off. Knocked off by what, I wanted to know - barracuda? shark? whale?
On a morning dive, one member of our party, Carol, a paramedic, came across a 30ft (harmless) whale shark. She was shaking when she climbed back on board. Mark, a race-horse trainer from Kentucky, had a nose-to- nose encounter with a curious barracuda. "Man, I held my knees to my chin and just kept that fish in front of me," he said. "No way was I letting that sucker get round my back."
Diving was a revelation. Like flying over a glorious garden with jewel- coloured fish-butterflies. But as I swam towards the coral floor, a piercing pain shot through my head. I tried holding my nose and blowing, but the only relief came by swimming upwards. I looked for my "buddy" (no one dives alone) and couldn't see him. Suddenly the ocean seemed a vast and lonely place to be. Panicking, I struck out for the underside of the boat, pitching in the waves some 40ft away. But the harder I swam, the further away it seemed. Finally, I reached the boat's ladder and clung on; safe, but feeling rather silly. My buddy said he had been below me all the time.
Back at the lodge it was almost time for cocktails. I wanted a nice lie- down first, so I wandered through the palm trees to the row of wooden cabins. One of the truly wonderful things about Small Hope Bay Lodge is the beds. They are huge, laden with pillows, and have perfectly placed reading lamps. Clean, fluffy towels are delivered daily and rooms are spotless, with doors opening on to the beach. All this more than makes up for the dodgy plumbing. Power-showers are more power-dribble, and the loo lurched alarmingly. One night it was home to a sweet little frog who had swum up round the U-bend. An exception to the eccentric pipework is the hot pool, a Jacuzzi set in a sun-deck and sheltered by mangroves. Bliss.
In the lounge, guests can help themselves to drinks, but at 6.30pm the staff get behind the old cut-in-half boat that serves as the bar, and hand out cocktails. Garvin's creations taste like rum-flavoured fruit juice; Skeebo - another divemaster, with an Eddie Murphy grin - pours pure rocket fuel. Platters of melt-in-the-mouth conch fritters are passed round and half-an-hour or so later everyone files into the dining room. Meals are sociably buffet-based and delicious: pasta Bahamian-style, baked with lashings of butter and cheese, lobster, curries, local fish, salads - and chocolate fudge cake with everything. This is not a place to diet.
Jeff Birch owns and runs Small Hope Bay on lines set down by his late father, Dick, who founded the lodge in 1960. Dick Birch also pioneered the resort diving course. "Anybody can dive," Jeff says. "It's just a matter of sharing information in a safe, uncomplicated way."
An hour's flight from Fort Lauderdale or Miami, Small Hope Bay lies off the world's third-largest barrier reef, and is popular with experienced divers. Americans pop down for the weekend, even for just 24 hours. Some novice divers, such as Mike - a decorator from Columbus, Ohio, and a fellow yoga trainee - find water to be their natural element. Mike trained on Sunday and by Friday was 185ft down; a depth which brought a sharp intake of breath from diving instructors I spoke to in Britain. There's a risk of nitrogen narcosis at these levels, where inexperienced divers can become dangerously over-confident. But the divemasters are vigilant, and in its 39 years, the lodge has never lost anyone through a diving accident.
Mike's dives included wrecks, caverns and one called "Over the Wall", where the sea floor drops 6,000ft. I stuck to the pretty coral gardens, forced by blocked sinuses to stay near the surface. Another beginner, Rolly Miller, 12, quickly lost any nervousness. "He saw sharks, so he was happy," said his mother, Marcia.
Sue swam down to 50ft, but developed ear problems. A week after we left, she sent me an e-mail from Kentucky. I could almost hear her, saying: "It was wonderful. But ah still have half that ocean in mah head."
Rachel Henry paid pounds 367.40 for a flight from Heathrow to Nassau via Miami with Virgin (01293 747747) and Bahamasair, plus $84 (pounds 52) return via Bahamasair to Andros Town. BA (0345 222111) flies direct to Nassau for pounds 399 if you book this month and travel before 30 June.
A week at Small Hope Bay Lodge (001 242 368 2013/4; e-mail: SHBinfo@SmallHope.com; website: www. SmallHope.com), costs $1,120 (pounds 700), full board; dive training is free, and each dive costs $45/$55. Diving packages are $1,510 per week for adults; daily rates available.
Jeff Birch will be on the Small Hope Bay Lodge stand (306E) at the London International Dive Show, at Olympia, today and tomorrow.
THE LONDON International Dive Show takes place today and tomorrow at Olympia, Hammersmith Road, London W14 (0171-385 1200 for details). Tickets cost pounds 5 per adult and pounds 2 for children under 14 and are available by credit card from Dive Show Ltd (0181-977 9878).
TO LEARN to scuba-dive in the UK, or for a list of dive centres, contact: British Sub Aqua Club (BSAC) on 0151-350 6200 (fax 0151-350 6215, website: www.bsac.com), or the Professional Association of Diving Instructors (Padi) - on 0117 300 7234 or 01179 710 400, or visit the Padi website (www.padi.com).
THE MINIMUM diving age is 12, but Padi has recently introduced a swimming- pool diving course called "Bubblemakers" for children aged 8 upwards.