lJaques-Yves Cousteau was born on 11 June 1910, in Saint-Andr-de-Cubzac in France. [], then when he was training to be a pilot a serious accident ended his aviation career. So it was the ocean that would win this adventurers soul. In 1936, near the port of Toulon, he went swimming under water with goggles. It was a breathtaking revelation.

Cousteau Society

The first time one snorkels or dives with an aqualung is a revelation. The sea, as well as freshwater lakes and rivers, is teeming with life and objects that are absolutely fascinating, and many of you may have toyed with the idea of snorkelling or diving at some point. But before taking the plunge it is important to be aware of the possible dangers involved and it would be advisable to take a course to gain the basic skills.

Snorkelling involves swimming with a facemask and a breathing tube. In spite of so many films that show people diving under water without facemasks but apparently seeing perfectly well, the human eye is not adapted to focusing clearly in water. A diving mask makes all the difference as it traps a layer of air between the eyes and the water, and vision becomes almost normal. You will be breathing air at atmospheric pressure. Simply lying face down on the surface (always remember to wear a T-shirt in the summer to protect your back from the sun) can be very rewarding, especially in tropical seas. Fish, crustaceans and corals are among the marvels for you to admire. But you might want to dive deeper with your snorkel and this is a little more complicated.

The mouth is connected to the inner ear by the Eustachian tube. As you go deeper, the air pressure increases and if the pressure between the mouth and the inner ear is different it can cause some degree of pain. So when ducking under the water you must clear your ears. To do this, simply hold the nose and the mouth shut and blow hard. This action opens the Eustachian tube and equalises the pressure. If you find you cannot do this at first, do not force yourself to go deeper as this could result in a burst eardrum. It would be better stay on the surface and try again later.

Another difficulty is that as buoyant as you may be on the surface, the lower you go the less bouyant you become until, at a depth of about ten metres, you have no bouyancy left at all. At this stage swimming back to the surface becomes more and more difficult. So do not be tempted to go too deep. After all, most of the water life is to be seen in the first 20 metres so there is no reason to try to go any deeper. On surfacing you will automatically breathe out quite strongly. This clears the water from your snorkel and allows you to breathe again.

More adventurous swimmers will be tempted to use an aqualung in order to spend some time at depth. This is an unforgettable experience but, again, there are some rules to follow. The first is to take a training course with an expert instructor. These courses are available all over Rome and in holiday locations. They are quite expensive, but is your safety worth quibbling over cost? Equipment is provided for these courses and it is certainly not a good idea to buy your own until you have been trained and are a confident diver.

Diving with an aqualung means that you will be breathing air under water at ambient pressure. The gases of the air, nitrogen and oxygen are more soluble in your blood at higher pressures and if you reduce this pressure too quickly, by surfacing too fast, it can cause very serious problems to your circulatory system. Your instructors will explain this more fully but it only becomes a real problem if you go below 20 metres.

Dont be put off by these warnings. Although it is a dangerous sport that claims lives each year, sub-aqua diving is one of the most thrilling and satisfying experiences available and provided the basic rules are followed it is quite safe. Enjoy it.

There are five golden rules that even highly-trained divers should not ignore.

Never dive alone. However skilful you are there could always be moments when you need help.

Never dive without a life jacket and make sure you know how to use it.

Always tow a divers buoy with you. Many divers have been seriously injured or even killed by motorboats whose drivers were unaware of divers beneath the surface.

Always wear a wet suit, (at least the top half). Even in the mediterranean summer at about 12 m the water temperature drops sharply from about 200C to about 80C and you can become helplessly cold in just a few minutes

Never enter a cave or wreck without an expert guide.

Your nearest swimming pool will have advertisements for such courses or you can contact ANIS Via Pietralata 120, tel. 064503300 or CMAS at Palazzo Coni, Viale Tiziano 70, tel. 0636858480.