At the moment of detonation there was a flash. At that instant I was able to see straight through my hands. I could see the veins. I could see the blood, I could see all the skin tissue, I could see the bones and worst of all, I could see the flash itself. It was like looking into a white-hot diamond, a second sun.

A glorious dawn broke over Christmas Island on 28 April 1958. I stuck my head out of our squat little tent on that morning along with hundreds of other servicemen who were taking part in Operation Grapple. Even at that early hour the tropical sun's rays were hot enough for us to move around shirtless and the sky was full of ugly cormorant sea-birds whose image decorated the operation's emblem. As I watched them flying around I never guessed for a moment that later the same day I would shovel up hundreds of their corpses with the eyes burned out of their pointed-heads after they too had witnessed a megaton nuclear explosion.

We were given a simple white cotton suit to pull on over our shorts and shirts while others just stood with their long trousers and khaki jackets. The sailors and the marines were, for the most part, dressed in normal gear with no special protection. This was to be the first nuclear bomb test which I'd ever witnessed and it would be the one and only time I'd ever be issued with any form of protective clothing. People claim we were issued with scientific equipment in the form of little badges or dosimeters which measured the levels of radiation we were exposed to but in my personal experience this did not take place. To this day I've still to wear one of these metering devices. I've also seen photographs of men wearing futuristic-looking goggles with hoods, taped-up seams and special boots who were reputedly stationed on Christmas Island during the nuclear bomb tests. Yet, in the year-long period I was on the island and throughout the five nuclear tests I witnessed, I never once clapped eyes on any such equipment nor, for that matter, any individual from the services wearing it.

On the morning of the test all the military personnel were gathered on to the main beach. We were told to sit down, relax and wait for further instructions from our commanding officers. The heat of the early morning sun made us very uncomfortable so we asked for permission to remove our cotton suits. But they told us to "Shut up and be quiet".

As I sat on the beach I started to become increasingly worried and all sorts of crazy thoughts raced through my mind. Two days previously I'd helped the Gilbertese villagers, most of the Fijians and the two WVS ladies, aboard the "safety-ship" HMS Messina. The Gilbertese couldn't wait to board the ship since they'd been promised the chance to go below decks during the test to watch Donald Duck and Mickey Mouse cartoons. As I helped one of the little WVS women to disembark from the landing craft she turned to me and said sweetly:

"We will pray for you all, God Bless."

These words had hit me like a slap on the face. I had never thought we were in any sort of danger until that very moment. But, as the date of the bomb test neared, lots of other soldiers who were braver than I ever was also started to get worried. ...

Suddenly, before I could have any more misgivings, a voice came through the tannoy:

"This could be a live run," it said dramatically. "Five ... Four ... Three ... Two ... One ... Zero ..."

There was a moment's pause. Then it happened.

"Cover your eyes!" bawled the voice from the loudspeakers. I had my fists shoved into my eyes and my back to the area where the bomb was going off. At the moment of detonation there was a flash. At that instant I was able to see straight through my hands. I could see the veins. I could see the blood, I could see all the skin tissue, I could see the bones and worst of all, I could see the flash itself. It was like looking into a white-hot diamond, a second sun.

Then the heat came. A slow, intense, searing heat which ate its way into your very bones. It didn't feel "... as if someone has passed an electric fire behind us". On the contrary, it felt as if someone had passed an electric fire through us. I let out a scream with the scorching pain.

"Okay, look at the bomb now," said the voice from the PA system.

The whole scene was unbelievable. A gigantic, dirty-looking mushroom cloud was forming on the horizon. An enormous ball of fire inhabited the base of the cloud and deadly-looking ripples of waves began to emanate from its base. It headed directly for us as we stood on the beach. I quickly glanced around me at the other men just as we got hit by a gale. Some tents got wrecked and the cookhouse collapsed.