He learned a few words, but mainly, Peter fell in love with her

The aim was for her to teach Peter, a bottlenose, to speak English

Of all the weird and wonderful events of the 1960s, few are as strange as an animal experiment that took place on the U.S. Virgin Islands in 1965.

For ten weeks, in a charming villa on the island of St Thomas, overlooking the Caribbean, Dr John C. Lilly, a neurologist, tried to teach a six-year-old dolphin to speak English.

His 23-year-old assistant, Margaret Howe, a Virgin Islands local, would live, day and night, with Peter, a bottlenose dolphin. And they would eat, bathe, sleep and play together in complete isolation.

What no one predicted is that Peter the dolphin would take it one step further. He didn’t get too far with his English, but he did fall in love — sexual and romantic love — with his teacher.

And next week, after nearly five decades of silence from Margaret Howe, a BBC documentary will tell the whole story.

By the time of the experiment, Dr Lilly had already written a 1961 bestseller, Man And Dolphin, claiming dolphins’ brains were 40 per cent bigger than ours and that, like us, dolphins trembled at pain and could control their anger. What’s more, he believed, they were capable of understanding human language.

Extraordinarily, he was also licensed by the American government to investigate the effects of LSD, and chose to inject it into two of the dolphins in his care in the Caribbean, though he was disappointed to find it appeared to have no effect.

The preparations for the Nasa-funded experiment into dolphins’ ability to ‘speak’ were extensive. First, Dr Lilly had the villa — Dolphin House — flooded with seawater, so that Margaret and Peter could live as one.

Telling tales: Margaret has spoken of her experience in the villa with Peter for the first time in decades

The water on the first floor was 22in deep, allowing Margaret to wade and Peter to swim. Margaret could climb out of the water to work at a desk suspended from the ceiling. At night, she lifted herself onto a hanging mattress, protected from Peter’s splashings by a shower curtain. She ate tinned food, so no need for any deliveries. No one was to interrupt their daily routine.

And what a rigorous routine it was, from Sunday to Friday, with only Saturdays off for Margaret. She lived her life in a swimming costume — with an extra leotard on colder evenings — and cut her hair to a quarter of an inch long to make her interactions with Peter easier.

The day began at 8am with Peter’s first English lesson. Margaret’s aim was to encourage him to mimic sounds which she taught him. They can make human-like sounds through their blowholes, and it was Dr Lilly’s aim to nurture that skill.

Margaret came up with the idea of painting her face in white make-up and black lipstick so that he could clearly see the shape of her lips moving.

Audio recordings of the experiment reveal how Howe encouraged Peter to greet her with the words ‘Hello Margaret’.

As she told documentary maker Christopher Riley recently: ‘“M” was very difficult. I worked on the “M” sound and he eventually rolled over to bubble it through the water. That “M” he worked on so hard.’

In time, he could pronounce an approximation of the words ‘one’, ‘we’, ‘triangle’ and ‘hello’, and eventually, when Margaret parroted ‘work, work, work’, he would reply ‘play, play, play’.

At 10am, Margaret and Peter would indeed play together in the pool. There were further lessons at 12pm and 3pm, with five pounds of fish at each session. In between, Margaret continued to play with Peter, inside the villa and in an outside tank, throwing balls and towels for the dolphin to fetch.

Peter was also a keen TV-watcher and would stare at a set she turned on at the side of the pool. During breaks, Margaret wrote her notes, prepared meals and did the housework.

To begin with, all went well, and Peter began to make progress with developing human-like sounds.

‘Peter is his energetic self and a bit nippy on the toes,’ she wrote in her diary, referring to the little nibbles Peter made.

‘I carry a long-handled broom with me for that and ward him off. This is not always the case: we have had several long “loving” sessions. The water is deep enough for him to roll over and this he does for tummy rubs. He sleeps just next to my bed.

‘Some nights he has been quiet and others he just has to yell and splash around. He is always hungry and usually wakes me early in the morning to tell me to feed him.’

Peter was becoming a touch naughty, too. Initially, he listened attentively as Margaret went through lessons devoted to counting and shapes. But, like a lot of unruly six-year-olds, he preferred to talk rather than listen. ‘He seems to have lost his sense of conversation,’ Howe wrote: ‘He often overrides me. I cannot teach him if he is going to yell every time I open my mouth. He has said, for the [recording] tape, one clear word, “ball”.’

Peter also spent a good deal of time staring at himself in a mirror. And, when Margaret answered the telephone, Peter got annoyed, making loud and competitive noises as she talked into the receiver.

Could Peter have been a little jealous? Certainly, he was getting close to her. By the second week, she wrote, Peter had grown much ‘more sociable, physical, making a thorough study of my feet, legs, ankles, knees. Doing this, he is very gentle, the rough part being when he tries to push me around’.

Peter was growing keener and keener on winning her attentions, hurling a ball against her shower curtain to get her to play. Increasingly, he only wanted to play ball with her and not on his own.

And then, in the fourth week, an alarming development occurred. As Margaret confided to her diary: ‘Peter has become sexually aroused several times during the week.

‘I find that his desires are hindering our relationship,’ she wrote. ‘He jams himself again and again against my legs, circles around me, is inclined to nibble and is generally so excited that he cannot control his attitude toward me.’

According to Andy Williamson, the vet who looked after the animals’ health at Dolphin House: ‘Dolphins get sexual urges. I’m sure Peter had plenty of thoughts along those lines.’

Now in a panic, Margaret returned Peter to a tank with two other dolphins, Sissy and Pam, to restrain him, and the period of exile seems to have worked because, on his return, Peter suddenly became gentle, sliding his mouth over her shin.

Peter, Margaret decided, ‘is courting me or something very similar. He presents his tummy and genital area for stroking. Perhaps this is his way of involving me in some form of sex play without scaring me away.’

As she tells Christopher Riley: ‘That relationship of having to be together sort of turned into really enjoying being together, and wanting to be together, and missing him when he wasn’t there.

‘I did have a very close encounter with — I can’t even say a dolphin again — Peter.’

The problem was that, just at the time Peter and Margaret had begun to hammer out a workable relationship, the experiment ended and the lab was closed.

Without funding, the fate of the dolphins was in question. They were shipped to Lilly’s other lab, in a disused bank building in Miami, Florida. It was a far cry from the relative freedom and comfortable surroundings of Dolphin House.

In Miami, Peter quickly deteriorated, and after a few weeks Margaret received the shocking news that Peter had committed suicide by refusing to breathe, and sinking to the bottom of his tank.

Was it the change in his surroundings, or could it have been that he was pining for the human he had grown so close to?

Vet Andy Williamson puts Peter’s death down to a broken heart, brought on by a separation from Margaret that he didn’t understand: ‘Margaret could rationalise it, but when she left, could Peter? Here’s the love of his life gone.’

Dolphins may not speak English — but, just like humans, they know all about broken hearts.

After the experiment with Peter ended, Margaret Howe left the laboratory and married the project’s photographer, John Lovatt.

Dr Lilly, although mocked by much of the scientific establishment, continued his researches into communication between humans and dolphins into the Eighties (he died in 2001).

He investigated other ways to talk to them, even attempting to use telepathy.

But after the extraordinary events in that sun-drenched laboratory in the Virgin Islands, no one ever tried to teach dolphins to speak English again.