Day of Trinity, a journalistic history of the explosion of the first atom bomb, detonates on a market nearly as barren of popular books on the subject as that strip of Los Alamos used for the first testing ground. The readable difference comes in the author's use of sources--some of his eye witnesses to the history of mass destruction were army staff stationed at the landlocked, padlocked top security laboratory in the desert. The ironic circumstances surrounding the building of the bomb are not scanted by the author. For instance, he juxtaposes his survey of the screening measures that were employed on soldier and civilian personnel at the base and the nevertheless undetected leakage of information to Russia by those who came through as clean--Rosenberg's brother-in-law Greenglass in the machine shop and Klaus Fuchs memorizing material at the big think sessions. This is a month-by-month record of the progress made by physicists working under war orders at war speed. The pressures were nearly unendurable and the army control exerted over the domestic lives of civilian scientists and their families was the last touch of madness to the Dali-esque landscape of insanity selected as a test site. Lamont follows up on the public and personal tragedies that came with the use of the bomb. Not the least of these is Oppenheimer's. The aftermath of treason trials and the tragic implications of the new force are also discussed. The readability factor is radioactive.