This is a 1957 book used to predict the devastation of nuclear bombs.  Included is a Radiation Exposure calculator in green color case stamped Calculators Radiac No 1; 6665-99-911-0117.  Book is the Army’s 579 page manual that explains devastation from nuclear bombs with many disturbing photos and charts.  If you lived in an area from a nuclear blast, this computer calculator will tell you the Dose Rate Roentgens per hour exposure.   Book reveals thermal energy, dynamic pressure, optimum burst and many more calculations to human loss and book shows pre / post photos & charts.  On reverse side of calculator are directions for use.  Calculator measures 5 inches in diameter and made of celluloid plastic in excellent condition.  Book is 9” x 6” x 1” with many photos of nuclear blasts, graph charts in very good condition.  Nuclear war is arguably the prevalent scare to our world from the 1940s to present day, but is a piece of our history when folks were guided into self preservation with a defensive mode like building underground bomb safes to school drills of hiding under a desk.  The potential of world wide nuclear war is still of concern.  This rarely found 1957 book with calculator reveals predictions pre to post aftermath of casualties will highlight any collection.