When the Fat Man atomic bomb exploded over Nagasaki on August 9, 1945, Dr. Takashi Nagai was working at a university hospital near ground zero. Having barely escaped from the dilapidated building and despite serious injuries, together with other doctors he began to provide assistance to the survivors. An account of the first terrible days after the atomic bombing formed the basis of the book “The Bell of Nagasaki.” Dr. Nagai died of leukemia two years after publication. His essay became both a unique eyewitness account of the disaster, and a scientist’s reflection on the nature of the atomic bomb, and a humanistic appeal: something like this should never happen again. The publishing layout of the book is saved in PDF A4 format.