Imagine climbing into an airtight, hollow metal ball and flinging yourself into the ocean to sink more than 3,000 feet below the surface. Your most high tech piece of equipment is a palm leaf fan used for air circulation.

In the 1930s Americans William Beebe and Otis Barton did exactly this using a metal cylinder called a bathysphere. Their base was Bermuda.

Marine writer Bradford Matsen brings to life this heroic and at times terrifying period of ocean exploration in ?Descent: The Heroic Discovery of The Abyss? released by Vintage Books in 2005.

The bathysphere dives were designed to collect new data about marine life that lived in the deeper depths of the ocean.

?Descent? has been labelled by reviewers as a book that is ?not for the claustrophobic. The inside of the bathysphere provided less space as the average broom closet. Dr. Beebe and Mr. Barton had to shimmy to get inside of it.

?Barton was quite thick and Beebe was slim,? said Mr. Matsen. ?They had to squeeze in and out of that thing. They would have to remain crouched in the bathysphere for several hours. For some of the deeper dives they would be in it for three hours.?

The first official bathysphere dive was in June 1930 several miles off of Nonsuch Island. At the time, no one knew if Dr. Beebe and Mr. Barton would survive the dangerous trip into the depths of the ocean.

?I described that dive in great detail,? Mr. Matsen said. ?They were shivering with fear. I didn?t overwrite it. It was terrifying and they had to be real brave.?

Mr. Matsen is the author of several marine and nature related books including Raptors, Fossils, Fins & Fangs: A Prehistoric Creature Feature, Fishing Up North: Stories of Luck and Loss in Alaskan Waters, The Incredible Hunt for the Giant Squid and Planet Ocean: A Story of Life, the Sea, and Dancing to the Fossil Record.

?My last project was a television series and book ?The Shape of Life? on the evolution of life in the sea,? said Mr. Matsen. ?I became interested in writing a children?s book about the bathysphere about three and a half years ago. As I was researching it I kept getting the same stories from everyone. It made me very suspicious. When everyone tells you the same story it means there is a much better story somewhere out there.?

Mr. Matsen?s project about the bathysphere turned into a book for adults. It was published on the heels of Carol Gould?s ?The Remarkable Life Of William Beebe: Explorer And Naturalist?.

However, the two books don?t really cross paths. While Mrs. Gould?s books focuses a great deal on Dr. Beebe?s personal life and other explorations, Mr. Matsen focuses almost entirely on Dr. Beebe?s bathysphere dives in Bermuda waters.

He goes little into Dr. Beebe?s personal life, but does explore the complex, often strained, relationship between Dr. Beebe and dive partner Otis Barton.

The bathysphere dives, which began around the time of the stock market crash of 1929 made headlines around the world. One of the dives was broadcast via radio. The creatures that Dr. Beebe described as living in the deep ocean were so incredible that at first, people accused him of making them up. His research was eventually authenticated and he wrote several books and papers about his 35 bathysphere dives.

Sadly, seventy years later, Mr. Matsen found the original bathysphere rusting in a junk heap under the cyclone ride on Coney Island, New York.

?It has been rescued as a result of my book and is now back on display,? he said. ?The New York Aquarium invited me out to witness a ceremony where it was reinstalled.?

To research ?Descent? Mr. Matsen came to Bermuda and stayed for a couple of weeks.

?I had a ball,? he said. ?I enjoyed it very much although the traffic terrified me. I saw people with wounds the first day I was there and fell in love with the buses. I went twice, for two weeks each time. I met Jeremy Madeiros, government conservation officer.?

Mr. Matsen toured Nonsuch Island, which was Dr. Beebe?s base during the bathysphere dives.

?I was so inspired by Nonsuch Island,? said Mr. Matsen. ?Although It didn?t look anything like it did in 1934 because it has been reforested. It was pretty much scrub when Beebe was there.?

?Descent? also looks at other people involved with the bathysphere dives including Gloria Hollister and John Tee-Van.

?The characters around William Beebe were fascinating,? said Mr. Matsen. ?Gloria Hollister started the Nature Conservancy in 1953. Mr. Tee-Van became director of the New York Zoological Society in 1956.

?On the Otis Barton side I got to know some of his family. He was a quirky, strange man.?

Mr. Barton tried on several occasions to film his dives with Dr. Beebe, but due to the total darkness of the ocean at deeper depths, failed each time. Unfortunately, Mr. Barton?s participation after the dives was often forgotten by the general public almost as soon as the dives were made. This was something that enraged Mr. Barton who had spent large portions of his fortune funding the bathysphere dives.

?I did get to know that part of Mr. Barton?s family,? said Mr. Matsen. ?I had a wonderful time doing the research for the book.?

Mr. Matsen said Dr. Beebe is probably better remembered in Bermuda than anywhere else in the world, despite his many important contributions to natural science. Mr. Matsen hopes that his book and Carol Gould?s book will help to change this.

?I give lectures on this all the time around the country,? said Mr. Matsen. ?I always say that this is not my story, it is their story. I just showed up at the right time to write it.?

?Descent? has met with some success and was an LA Times book prize finalist.

Mr. Matsen?s next book will be about another ocean explorer who came to Bermuda, Jacques Cousteau , but will focus more on his adventures in the Mediterranean.