The Last Unexplored Place on Earth: Investigating the Ocean Floor with Alvin the Submersible

Gr 4-7--People have explored every continent in our world, and yet the ocean is still mostly untouched. That's where the submarine Alvin comes in. The vessel has helped discover amazing things in the ocean, such as the Titanic's wreckage, volcanic ridges, wrecks at the bottom of the Black Sea, seemingly impossible life at the bottom of the ocean, and more! All of this is possible in a tiny sub that only fits three people and can go up to 21,000-ft below the surface of the ocean. This fascinating book gives the history of the Alvin sub and how its invention and upgrades have now made it possible to explore up to 99 percent of the ocean. It has been around for 50 years and is still making amazing discoveries. This book is not just about the sub, but about the scientists who have been lucky enough to ride in it and the discoveries they've made. The book includes an expansive bibliography featuring recorded archives and interviews, books and articles, press releases, government documents, and more. Within each chapter there are reference excerpts with interesting side notes, fact bubbles, and lots of photographs from Alvin's journeys. Some of the reference bubbles are a little hard to read as the words seem to run into each other. VERDICT A comprehensive and engaging addition to nonfiction sections, where subjects like exploration, engineering, and oceans are popular.--Kristin J. Anderson