As “Avatar” continues to make box office history, James Cameron is eyeing a slice of history for a potential helming gig.The “Avatar” director has optioned Charles Pellegrino’s upcoming nonfiction tome “The Last Train From Hiroshima: The Survivors Look Back” with his own personal funds. While in Japan in late December promoting “Avatar,” Cameron asked 20th Century Fox for a day off Dec. 22 in order to visit Tsutomu Yamaguchi, one of the last survivors of the U.S. bombings of Hiroshima and Nagasaki during WWII. Yamaguchi died Monday at the age of 93. Pellegrino’s book, published by Henry Holt, is set to hit bookstores Jan. 19. Advance reviews have been glowing for the title, which takes place over two days and weaves together eyewitness accounts of the Japanese civilians and American pilots who experienced the atomic explosions firsthand. According to the book, 30 people are known to have fled Hiroshima for Nagasaki — where they arrived just in time to survive the second bomb. Yamaguchi was the sole survivor who experienced the full effects of the detonations at ground zero both times. At this point, project is not set up at Fox or Cameron’s Lightstorm Entertainment.