Produced by Gregory Walker
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by The Manhattan Engineer District, June 29, 1946.
Index
FOREWORD
INTRODUCTION
THE MANHATTAN PROJECT INVESTIGATING GROUP
PROPAGANDA
SUMMARY OF DAMAGES AND INJURIES
MAIN CONCLUSIONS
THE SELECTION OF THE TARGET
DESCRIPTION OF THE CITIES BEFORE THE BOMBINGS
Hiroshima
Nagasaki
THE ATTACKS
Hiroshima
Nagasaki
GENERAL COMPARISON OF HIROSHIMA AND NAGASAKI
GENERAL DESCRIPTION OF DAMAGE CAUSED BY THE ATOMIC EXPLOSIONS
TOTAL CASUALTIES
THE NATURE OF AN ATOMIC EXPLOSION
CHARACTERISTICS OF THE DAMAGE CAUSED BY THE ATOMIC BOMBS
CALCULATIONS OF THE PEAK PRESSURE OF THE BLAST WAVE
LONG RANGE BLAST DAMAGE
GROUND SHOCK
SHIELDING, OR SCREENING, FROM THE BLAST
FLASH BURN
CHARACTERISTICS OF INJURIES TO PERSONS
BURNS
MECHANICAL INJURIES
BLAST INJURIES
RADIATION INJURIES
SHIELDING FROM RADIATION
EFFECTS OF THE ATOMIC BOMBINGS ON THE INHABITANTS OF THE CITIES
APPENDIX: Father Siemes' eyewitness account
This report describes the effects of the atomic bombs which weredropped on the Japanese cities of Hiroshima and Nagasaki on August 6and 9, 1945, respectively. It summarizes all the authentic informationthat is available on damage to structures, injuries to personnel,morale effect, etc., which can be released at this time withoutprejudicing the security of the United States.
This report has been compiled by the Manhattan Engineer District of the
United States Army under the direction of Major General Leslie R.
Groves. Special acknowledgement to those whose work contributed
largely to this report is made to:
The Special Manhattan Engineer District Investigating Group,
The United States Strategic Bombing Survey,
The British Mission to Japan, and
The Joint Atomic Bomb Investigating Group (Medical). and particularlyto the following individuals:
Col. Stafford L. Warren, Medical Corps, United States Army, for hisevaluation of medical data,
Capt. Henry L. Barnett, Medical Corps, United States Army, for hisevaluation of medical data,
Dr. R. Serber, for his comments on flash burn,
Dr. Hans Bethe, Cornell University, for his information of the natureof atomic explosions,
Majors Noland Varley and Walter C. Youngs, Corps of Engineers, United
States Army, for their evaluation of physical damage to structures,
J. 0. Hirschfelder, J. L. Magee, M. Hull, and S. T. Cohen, of the Los
Alamos Laboratory, for their data on nuclear explosions,
Lieut. Col. David B. Parker, Corps of Engineers, United States Army,for editing this report.
Statement by the President of the United States: "Sixteen hours ago anAmerican airplane dropped one bomb on Hiroshima, Japan, and destroyedits usefulness to the enemy. That bomb had more power than 20,000 tonsof T.N.T. It had more than two thousand times the