ATOMIC ENERGY THURSDAY DECEMBER 6 1945 UNITED STATES SENATE SPECIAL COMMITTEE ON ATOMIC ENERGY Washington D 0 The special committee met pursuant to adjournment at 10 a m in room 312 Senate Office Building Senator Brien McMahon chairman presiding Present Sena tors McMahon chairman Russell Johnson Millikin Hickenlooper and Hart Also present Representative John R Murdock Edward U Condon scientific adviser and James R Newman special assistant to the special committee The CHAIRMAN The hearihg will come to order We will hear Dr Morrison · STATEMENT OF DR PHILIP MORRISON PHYSICIST LOS ALAMOS LABORATORY · Dr MORRISON I have a prepared statenrent I believe it is appropriate to indicate my qualifications before I begin After the completion of my graduate work at the University of California in Berkeley in 1940 I was for a short time instructor in physics at San Francisco State College and later at the University of Illmois In December 1942 I began work at the metallurgical laboratory of the· University of Chicago In October 1944 I came to the Los Alamos laboratory At Chicago my work consisted of theoretical £ xperimental and design work in connection with the p_lutonium-producing chain reactors At Los Alamos it was concerned with the active components of the bomb itself Following the Trinity test in New Mexico I went to the Marianas to assist in the final assembly work on the bomb On September 6 I came to Japan to join Gep eral Farrell's party there I returned to Los Alamos in October Senator MILLIKIN Mr Chairman who is General Farrell Dr MORRISON General Farrell was General Groves' deputy he was -sent overseas to head the military party Many Americans have visited the cities or the ruins of Japan since the end of war in the Pacific The reporters and the photographers have made clear for us all the appearance of the war-damaged towns especially of the cities destroyed by the first atomic bombs Hiroshima and Nagasaki But there is more to be learned from those scenes than the newspapers have yet been able to tell It was my job to visit the damaged cities of Japan to speak with the people there and to assist in the carrying out of certain technical studies You have heard and 233 234 ATOMIC ENERGY you will hear more expert testimony on the kinds and extent of the damage done by the atomic bomb I am a nuclear physicist not a specialist on this or that kind of damage I wish I knew even less about damage than I do It is my purpose to tell the committee as clearly as I can what the impressions of an American physicist are when he views the ruins and talks to the survivors of the bombing he and his coworkers spent so much time to make possible The atomic bomb is not merely a new weapon it is a_revolution in war I saw the blackened ruins of Tokyo and Osaka of Kobe and of Nagoya and I know th'ht a city cannot live under the fire raids of a thousand B-29's The destruction of a great city in itself ·is not the new feature of the 'atomic bomb To make clear why the atomic bomb is different one must talk first of the B-29 We of the Los Alamos project who went overseas in July to prepare the· bombs for delivery over the target were stationed on the small island of Tinian near Saipan in the Marianas chain Tinian is a miracle Here 6 000 miles from San Francisco the United States armed forces have built the largest airport in the world A great coral ridge was ·half-leveled to fill a tough plain and to build 6 runways each an excellent 10-lane highway each almost 2 miles long Beside these runways stood in long rows the great silvery airplanes They were there not by th t dozen but by the hundred From the air this island smaller than Manhattan looked like a giant aircraft carrier its deck loaded with bombers I have fl9wn many times in a B-29 and I doubt that there is a more complex and wonderful machine of any kind And here far from the factories in Seattle or Wichita were several hundred of these milliondollar craft Here were collected tens of thousands of specialists trained in the operation and repair of the delicate mechanisms which cram the body of the plane In the harbor every day rode tankers laden with thousands of tons of aviation gasoline A net of pipe lines supplied the airfields with fuel The radio dial was busy with signals of every kind And all these g'igantic preparations had a grand and terrible outcome At sunset some day the field would be loud with the roar of the motors Down the great runways would roll the huge planes seeming to move slowly because of their size but far outspeeding the occasional racing jeep One after another each runway would la nch its planes Once every 15 second another B-29 would become air-borne For an hbur and a half this would continue with precision and order The sun would go bdow the sea and the last planes could still be seen in the distance with running lights still on Often a plane would fail to make the takeoff' and go skimming horribly into the sea or into the beach to burn like a huge torch We came often to sit on the top of the coral ridge and watch the combat strike of the 313th wing in real awe Most of the planes would return the next morning standing in a ·1ong single line like beads on a chain from just overhead to the horizon You could see 10 or 12 planes at a time spaced a couple of miles apart As fast as the near plane would land another would appear_ at the edge of the sky There were always the same number of planes in sight The empty field would fill up and in an hour or two all the planes would have come in ATOMIC ENERGY 235 Next day the reconnaissance photographs would come in They showed a Japanese city with whole square miles of it wrecked and torn by flame The fire bombs dropped on wood and paper houses by the thousands of tons had done their work A thousand B-29's time and again burned many square miles of a city in a single raid The atomic bomb was something els·e There were no shiploads of incendiaries Instead of all the ordnance men and their bomb dumps there were about 25 people from Los Alamos a few Quonset huts transformed into testing laboratories and a barricaded building The strike took off after midnight The field was deserted Only two or three planes were warming up A few lights burned aroun d a single hard-stand Senator MILLIKIN What is a hard-stand Dr MORRISON It is a path on the airfield on which the airplane sits before taking off And one plane roared down the runway took off and set course for the cities of the enemy The reconnaissance photos next told the same story One plane with one bomb had destroyed many square miles of a city destroyed them even more thoroughly and with even less chance for resistance or escape than the 1 000-plane strike I can imagine a thousand atomic bombs and an airport like Tinian's to send them off But not even the United States could prepare a thousand Tinians with ordinary bombs There are simply not enough people Destruction has changed qualitatively with this new energy War can now destroy not cities but nations There is even more to be said I remember vividly the lunch we had at the prefectural building in Hiroshima The Japanese officials came there to talk to us and to describe their experiences I sat at lunch next to and spoke to the chief medical officer of the district He had been pinned in the wreckage of his house for several days after the explosion He lived a little more than a mile from the point o f impact and was still wearing splints His assistant had been killed and his assistant's assistant Of 300 registered physicians more than 260 were unable to aid the injured Of 2 400 nurses orderlies and trained first aid workers more than 1 800 were made casualties in a single instant It was the same everywhere There were about_ 33 modern fire stations in Hiroshima Twenty-six were useless after the blast and three-quarters o f the firemen killed or missing The military organization was destroyed the commanding general and all his staff were killed with some 5 000 soldiers of the garrison of 8 000 Not one hospital in the city was le ft in condition to shelter patients from the rain The power and the telephone service were both out over the whole central region of the city Debris filled the streets and hundreds even thousands o f fires burned unchecked among the injured and the dead No one was able to fight them Senator MILLIKIN What was the population o f Hiroshima Dr MoRRISON About 300 000 There is a word for this kind o f attack it is described as an attack o f saturation If you strike at a man or a city your advero·ary protects himself If you attack a man he runs or strikes back at you if you attack a city it throws up flak it musters its firemen it treats the wounded But i f you strike all at once with overwhelming force your enemy cannot protect himsel f He is stunned The flak bat- 236 ATOMIC ENERGY teries are all shooting as fast as they can the firemen are all busy throwing water at the flames Then your strike may grow larger without incre11sed resistance The defenses are said to be saturated The atomic bomb is a weapon of saturation It destroys so quickly and so completely such a large area that defense is hopeless · Leadership and organization are gone Key personnel are killed ·with the fire stations wrecked and firemen burned how control a thousand fires With the doctors dead and the hospitals smashed how treat a quarter 0£ a million injured · There is one more novelty A Japanese official stood in the rubble and said to us All this from one bomb it is unendurable We learned what he meant The cities 0£ all Japan had been put to flame by the great flights 0£ B-29's from the Marianas But at least there was warning and a sense of temporary safety If the people in Kobe went through a night 0£ inferno you living in Nagoya were going to be all right that night The thousand-bomber raids were not concealed they even formed a pattern of action which the war-wise J apanese could count on But every hour of every day above any Japanese city there might be one American plane And one bomber could now destroy a city The alert would be sounded day and night Even i£ the raiders were over Fukuoka you in Sendai a thousand miles north must still £ear death from a single plane This is unendurable I should like to interpolate a few remarks on the kind 0£ damage that the bomb does I think I can describe to you very simply what happens and that will make clearer to you what we saw there ·when the bomb is detonated in the middle 0£ a city it is as-though a small piece 0£ the sun has been instantly created There is formed what' we have called the ball 0£ fire which is a hot glowing mass something about one-third of a mile across ·with a temperature of about a hundred million degrees Fahrenheit in the center 0£ it The effects from this small sun are as you would expect In the first place there is a sudden creation and expansion which pushes away with terrible violence the air that once occupied this region This air shocked into motion as we say moves just like a blast _wave from a great explosion of TNT We often measure the effectiveness 0£ a bomb in tons of TNT equivalent This pushing air creates an enormous pressure even a great distance away Behind the wave 0£ pressure which travels rapidly through the air there come great winds 500 to 1 000 miles per houT winds which damage and destroy all structures If you stand near this piece 0£ the sun-Senator Mn LIB IN Those are the winds rushing to fill the vacuum is that right Dr MORRISON They are winds which occur paTtly from that sir and also partly because the wave starts in the air It runs too fastthe air cannot move fast enough to keep up with the wave so it follows somewhat like a breakwater wave and this is the great wind Senator MILLIKIN I see Dr MORRISON I£ you are near the sun you must expect to get buTned The people near it are burned on the body the people and the structures underwent terrific radiant heat _ In New Me-xico ·where we were 10 miles away on a cold desert I felt as though the hot sun had been out for an hour when the explosion occurred My £ace was warmed up ATOMIC ENERGY 237 There in Japan the same effect happened Since they were closer there instantly all organic material was burned up For some distance it burned up the flesh As I shall show later in my prepared statement for a considerable distance it set fire to piece of wood curtains textiles to anything inflammable in the neighborhood There are two more effects At the instant of the explosion there is emitted from this small sun not only the great push through the air the violent blast which is the violent explosion-there is not only the concentrated heat which you would expect from being clos·e to the sun there was also a great amount of radiation like the radiation used by doctors like the X-ray radiation used fO'I' tne treatment of cancer This radiation is very penetrating Th re is no protection behind a foot of concrete for example Senator MILLIKIN How about lead Dr MoRRISON It is possible to have protection It depends on where you are You will have no protection unless the material is thick enough If you have 20 feet of concrete or 5 feet of lead you are ' safe enough if it is in front of you This radiation produces special physiological effects which I would like to describe There is oue more effect which may or may not be effective in a militar y sense besides the instantaneous burst of these ray--like emanat10ns There is left on the ground an enormous amount of radioactivity corresponding in the maximum case to thousands of tons of radium If this is the case if this is deposited on the ground it will pe difficult to approach that area that region for a long time Senator MILLIKIN Mr Chairman I have a question Would it disturb your sequence of thought if I would go into the lead matter now Dr MORRISON No sir Senator MILLIKIN Are there any other readily available metals that could be used to shield things that could be used as a defense against the atomic bomb Dr MORRISON The only point is getting enough material It doesn't matter what it is if you have enough of it It may be concrete dirt 0r lead whichever it is is not very important Lead of course is very heavy and to get a mass of material is convenient with lead Senator MILLIKIN In other words a thin sheet of-lead may be equivalent to 2 or 3 feet of some other material Dr MORRISON I am afraid not An inch of lead is equivalent to 10 inches of concrete The factor of lead to concrete is about 1 to 10 Gold would be twice as good Senator MILLIKIN What does the person wear if he goes into one of these infected areas Dr MORRISON I don't know I don't quite understand - There is nothing you wear for protection Senator MILLIKIN I saw a picture in a paper of a tank that moved in there in New Mexico and it said that the tank was coated with lead or something of that kind Dr MotmISON Yes Senator MILLIKIN Now when the men get out of that tank what do they wear 238 ATOMIC ENERGY Dr MoRRISON 'l'hey didn't get out They would have been fried i_ f they had gotten out at that time They stayed in Senator MILLIKIN Do you see a field of considerable usefulness where defensive measures are concerned in lead or any other metals Dr MORRISON Well going underground would be helpful I think that lead is especially valuable lead is useful if you have a small room and you want to keep it small Otherwise you might as well make it with concrete We have a similar problem when it comes to sealing in all plutonium reactors As far as I know except for instruments there lead is riot employed These other materials are cheaper You see it is much cheaper to use 10 feet of concrete than its equivalent in lead Senator MILLIKIN Thank you ' Dr MORRISON As I was saying there is left on the ground under some circumstances this large radioactivity In New Mexico where the explosion was on the surface this activity was sizable In both cities of Japan this activity was negligible simply because of the tactical choice of the method of employing the bomb It has been described in the press In New Mexico the bomb was • detonated close to the surface in Japan a considerable distance above the ground In one case the radioactivity was concentrated on the ground in the other case in Japan it was spread over a great area ai d so there vas not enough of it it was negligible Senator HICKENWOPER May I ask a question The CHAIRMAN Yes Senator Senator HICKENLOOPER How far away did the heat generated from the bomb kill individuals At say the 100-foot level in New Mexico as compared to the 1 500- or 1 800-foot level over these Japanese cities what would be the comparison Dr MORRISON Would you please wait I think I have that question covered in my statement Senator HICKENWOPER Yes I don't want to disturb your train of thought · Dr MORRISON Yes sir I answer that question directly in the statement · I simply want to give a picture of what the physical effects were and then I have this prepared statement from observations in the area of damage Senator JoHNSON You left out one step · Could you tell us something about the reaction I suppose that the air rushes back into· the vacuum That' c you describe the air as being pushed out at the time of the explosion Now there must be the secondary reaction of air rushing back in and Gausing damage through that suction that would follow naturally Dr MORRISON Mostly there is nothing left y that time to damage If you built one in between the two it might suffer some damage Senator JOHNSON The buildings are all torn down'but that suction is relatively something that will not amount to very much because the damage is all done Is that the theory Dr MORRISON That is right Senator JOHNSON But is there Iiot a tremendous suction ATOMIC ENERGY 239 Dr MORRISON There is but not too much effect where individual buildings were concerned We could sometimes see buildings where at the edge the air blast had struck from behind not in the front That effect would depend upon the shape of the building and such freak effects might happen Mostly the impact like a hammer causes the damage and following this hammer blow is the rapid wind after that the suction phase is not very important ·• Senator JOHNSON We have had described to us here cases involving concrete buildings reinforced by steel We have been told that the interiors of the buildings and the partitions had all be n torn out It just occurred to me that that reaction perhaps did that Dr MoRRISON That is quite likely I was just going to say that in the next sentence Senator MILLIKIN Mr Chairman pursuing that same subject a little further I have seen many pictures of dama e over in London during the bombing which showed that the builctings collapsetj towards the location of the bomb The explanation was that it was caused by the suction rather than by the hammer effect of the blast Does that prevail abo as far as this particular bomb is concerned Dr MORRISON No I don't believe it does It is rather less important in this case than· in small explosions · S3nator MILLIKIN I was curious about that Dr MORRISON I think that the effect has been exao-gerated even in the smaller explosions If I might put it this way the bigger the ex- plosion the more negative the effect of the suction phase the less important it is Senator MILLIKIN You get the first hammer effect which does the job and the second effect has nothing to pull down Dr MORRISON Yes The darriuge done in the cities struck by the atomic bomb is not easy t-0 realize Houses and buildings for a mile in all directions are totally destroyed A good deal of comment has been attracted by the ferro_concrete structures whose walis still stand These are very strong buildings But they too are u eless I have been in these buildings The window casements are gone the intE rior walls are down the roofs are collapse the furniture battered plumbing fixtures and heavy machinery overturned A great blast wind followed the shock and ripped through the b uildings destroying their interiors Most of them burned Brick buildings apd even steel-frame buildings with brick walls are extremely vulnerable Senator MILLIKIN Did I understand you to say a while ago that this wind you have described reaches ti velocity of 500 or 600 miles Dr MORRISON That is a very conservative figure A 1 000-miles wind is common Senator MILLIKIN What is a hurricane wind Dr MORRISON About 120 miles an hour Senator MILLIKIN I wanted that just for a comparison Dr MORRISON At Nagasaki the Roman Catholic church was an old and heavy brick-walled building nearly a mile and a half away and it suffered total destruction It is likely that an American city would be as badly' damaged as a Japanese city though it would look less wrecked from the air n Japan the wreckage burned clean in a 240 ATOMIC ENERGY western city the rubble would still stand in piles in streets But the city would be just as ruined and the people of the city as dead The action of the blast on steel-frame factory structures is known from the wreckage of t e Mitsuibishi Torpedo Works in Nagasaki Japanese homes are lightly built but their factories are about like ours And the torpedo works buildings collapsed in a twisted jumble of steel onto the heads of the workmen and the still-turning machines For a good mile and a half all factory structures were totally destroyed For 3 or 4 miles from the point of impact there is heavy damage making half the buildings unusable In Hiroshima the fires which began after the blast some set by overturned stoves and chimneys some by the heat from the bomb itself burned for 10 hours The flames stopped at the edge of the river Many places were completely destroyed by fire which had only been partly smashed by the blast It is not ha d to understand that fire-fighting was impossible S nator MILLIKIN Mr Chairman I hate to interrupt so often Dr MORRISON That is all right Senator MILLIKIN Yesterday we were questioning a witness as to whether these same effects would occur in a heavily constructed area like lower Manhattan for example I think I asked the question whether the great bulk of the heavy construction the buildings would serve to insulate and confine the effects of the blast Would you mind giving us your impression on that i · · Dr MORRISON As the blast wave moves over the face of the city it loses energy by the knockjng over of structures it carries debris around therefore I think the more densely the city was built up the more the number of buildings that would be caught in a given area Therefore the extent of the damage would be or might be somewhat smaller because there w re more buildings Senato MILLIKIN But the effect in a quantitative way would be the same1 · Dr MoRRisoN Yes sir Senator JOHNSON What is the direction of this blast i Is it straight down Dr MORRISON It depends on where you are and where the bomb is set for I am not sure that 1 can go into the details but if it is close it is straight down if it is some distance away it is horizontal Senator JoHNSON Of course this straight-down blast might raise havoc with the roofs but it might not raise havoc with the walls of the buildings Dr MORRISON That is true For example in Hiroshima the walls directly under the impact were intact while the roofs had been driven straight down The heat and the radiation had killed the people but the walls and even the telephone poles were still standing up The effect of course depends very much on how far away it is At some distances you have one effect and at some other distances you have another Senator MILLIKIN Is it true that so far as the bomb is concerned it throw out passing what is below it as far as the bomb itself energy in equal directions or does it have that energy thrown out directionally ooes ATOMIC ENERGY 241 Dr MoRRISON If the bomb is released very far above the earth it would throw out the same energy in all directions It is not as a matter of fact done this way but I would not like to go into that question Even more striking than the damage to buildings is the great number of casualties Very few people were in shelters because there was evidently no large bomber raid Virtually all the people in the streets within almost a mile were instantly and seriously burned by the great heat of the bomb These burns covered all the exposed flesh sometimes even clothing caught fire and burned the wearer fatally I remember seeing one man a patient who hail worn a railway worker's uniform This uniform in Japan is a dark serge with an insigne to designate his grade This man wore as insigne a kind of a crossshaped emblem over the left breast · His whole body was burned very badly and blackened with the exception of the region under this cross That was because the white clothing passed the heat somewhat less than the dark clothing did The dark clothing absorbed the heat and caught fire and burned him Of course the white clothing would ordinarily not do this There were reported to me some people who had even been wearing striped clothing upon whom they found the body had been burned in stripes I did not see that People inside buildings were not burned by the flash but were for the rriost part killed or seriously injured by falling wa lls and beams Caught in the wreckage of their homes many were burned to death by the secondary fires Those fires resulted fron i combustion material set ablaze after hundreds of stoves had been overturned this was in addition to the fires started by the bomb itself Of these people within a thousand yards of the blast about one in every house or two--- perhaps 5 or 10 percent--escaped death from blast or from burn By chanc-e these people were screened from the heat of the bomb by some object too light or too strong to kill' them by falling upon them Many literally crawled out of the wreck of their homes relatively uninjured But they died anyway They died from a further effect the effects of radiumlike rays emitted in great number from the bomb at the instant of the explosion This radiation affects the blood-forming tissues in the bone marrow and the whole function of the blood is impaired The blood does not coagulate but oozes in many spots through the unbroken skin and internally seeps into the cavities of the body The CHAIRMAN Would there be a third-degree burn Dr MORRISON 'NO j not from radiation j no burns at all There were some dramatic cases of people who were protected from the burns-The CHAIRMAN You mean the skin would be absolutely normal and yet the blood would be coming through Dr MORRISON Yes There might be a slight burn on the skin but it was not essential The white corpuscles which fight infection disappear 'Infection prospers and the patient diesi usually 2 or 3 weeks after the exposure · I am not a medical man but ike all nuclear physicists I have studied this disease a little It is a hazard of our profession With the atomic bomb it became epidemic 1 242 ATOMIC ENERGY The facts and figures of this and other related effects o f the atomic bomb are still under study and remain for the time being classified information I am not a medical expert in these matters and I have tried to tell you only the things I have seen It goes without saying that like most of the scientists of the project I am completely convinced that another war cannot be allowed A working and realistic domestic policy ought to be determined on the premise that some measure of international control of atomic energy will come and come immediately based on functioning matsrial agreements among the great and the smaller powers We have a chance to build a working peace on the novelty and the terror of the atomic bomb ·But 1 should not be a physicist if I le ft you with the impression that only in war a revolution has been made by the large-scale release of atomic energy Man will not live the same again for this advance I do not think you will soon see atomic automobiles though you may soon see atomic rockets and atomic power plants But the changes which will come are sure and great · and beyond prediction When science learned to control mechanical and thermal energy we had the early nineteenth century maturing of the industrial way of life Vhen science learned co qtrol over electrical energy we had the manifold changes which electricity has brought to daily life and to the structure of nations When the chemists understood the nature of chemical energy there was opened the way to new materials to frP dom from the restrictions of mine and farm to the changes which chemistry is even today still bringing us Now we have nuclear energy based on a more profound insight into and control over the fundamental nature of matter itself We have seen war change onl v 6 years after the key laboratory discovery in this realm We physicists are professionals in change and in novelty That new times will co me is our firmest conclusion Senator HART Mr Chairman The CHAIRMAN Senator Hart Senator HART Doctor when you compared in your statement an attack by 1 000 B-29's and one B-29 you said there was a great qualitative change in the destruction Then you followed with your observations on Hiroshima and about the only thing you said to support that statement was about the damage done by the gamma rays We had been led to believe from other testimony that when the bomb explodes well off the earth as was the case there that the gamma rays' damage is a very small proportion of the total damage Dr MORRISON I think I detected two questions in your question Would you mind if I separated them and tried to answer as I see them separately Senator HART Yes sir J r MoRRrsoN he y u gradually increase something by simply p1lmg on by quant1tat1ve 1mplementat10n you come to a point where something new has occurred and we have a qualitative chanae 0 For instance if you heat water you heat it 1 ° at a time until 'it boils and there is still a quantitative change going on But if you keep on heating _ you get a qualitative change it is no lopger water you have somethmg new ATOMIC ENERGY 243 The reason I say that the bomb has made a qualitative change is the manner in which the atomic bomb works Take the destruction of cities When you use ordinary bombs to destroy a city you do it with a great effort all the resources of a nation With the atmoic bomb it is done more or less with the left hand I mean one bomb one city The whole attitude has been changed They are not_ talking about the destruction of one city at a time any more the new strategy will have to deal with weapons of destruction which will make one city too small a target In the future it will not_ be the case of a raid against Berlin or against Hiroshima or Nagasaki on separate days but it will be against all of them on the same day · Senator HART It seems to me still that you are terming as qualitative a change which I consider a quantitative change Dr MORRISON Well this is a question of philosophy What I am implying is that by the piling on quantitatively you have produced a new-mode of action which is in nature qualitative As you know you might say an army is a collection of say 1 000 000 men But if you have a collection of 1 000 000 men into an army you have something different from just a collection of 1 000 000 men In the same way when you have a collection of atomic bombs you have something different then which becomes a qualitative difference because there you have a chance to destroy whole nations Senator HART Well I will drop that Doctor although I still think you mean quantitative rather than q_ualitative Do I understand you to say that the gamma £actor in your explosion is not a material part that mostly it is blast and heat Dr MoRRISON This is correct Senator HART Is that correct Dr MORRISON This is correct The gamma radiation is a part of it or could be it all depends upon how the bomb is used as I said The way the bomb would be normally used I do not think that the gamma rays would be material ·of course I do not know what the statistics are In the case of Japan under the conditions that existed there there are simply no records no officials men familiar with the· town who could tell us exactly what happened It is known that in Hiroshima 40 000 people came into the town the day before the bomb was dropped to help evacuate it because the town was on the list and they felt it would be attacked and they wanted to evacuate it They had started ·work at 7 o'clock in the morning they were still moving shops and furniture and the contents of warehouses and so forth and they were killed by the bomb However no census taker no statistician is able to say how many people were killed in that explosion It is my impression gained as I walked through the city and the hospitals and talked to the men that there was one man who escaped immediate death out of every one or two houses that were destroyed There was always someone who by chance escaped the building falling on him and killing him who by chance escaped the burns even from the direct heat or through the fires that raged throughout the· district There were people who 244 ATOMIC ENERGY walked away niore or less unharmed by chance-and even these did not escape death in the end Senator HART Doctor in the latter part 0£ your statement when you went into the political field I believe you used the words that something must immediately be accomplished in our international relations so that atomic bombs would not be used What is your thinking around that word immediately l Is that altogether a theoretical idea or have you some practical ideas about that Dr MORRISON I think £or example that the implementation 0£ the Three-Power Declaration i£ it comes in the near future and i£ it is extended will be an immediate step in the right direction I did not mean that the problem would be solved immediately I mean that we should act at once The reason I think that is this that one 0£ the grertt advantages that we have with regard to the control 0£ this decisive weapon which does not adhere to any other weapon is that it is something new · It is something which is not all over the world There are no great industries connected with it it is not filled with a tradition of continuity it does not have a tradition of money or economics-those interests do not enter into it There is none 0£ this J think that i£ we catch hold 0£ tli is opportunity and soon begin control you will find it to be a much easier situation to handle than if we sit around 1 year 3 years 7 years 10 years making no progress Then when it has come to a foll-fledged realization by that time there will be greater difficulty It will be widespread there will be money in it there will be great industries and the economy of great regions may be dependent on it It will be sizable and it will be great and it will be difficult to make such changes as should be made because then at that'time people will say that it is not practical Senator HART I take it that you did not think that there was an immediate and complete solution practical Let me ask you one thing Your statement has been about the power the destructive power of the atomic bomb alone In your thinking do you place that in a ifferent category than £or instance an entirely merciless bacteriological form of warfare · · Dr MORRISON Y ff sir I do Senator HART Why Dr MoRRISON I am not a bacteriologist and perhaps I am wrong but I have been in Washington on military affairs and on these matter I have spoken to people that know-The CHAffiMAN 1 defer to your greater knowledge Senator about the propriety 0£ an open session to a discussion 0£ bacteriological warfare Senator HART I am merely asking a· general question I£ he is going into anything that he ought not to go into I will withdraw the quest10n · The CHAIRMAN You are acquainted with that _Dr MoRRisON Yes sir I will not discuss it The CHAIRMAN I just wanted to caution you Dr MORRISON Yes sir thank you very much I simply wanted to say that the absence of successful bacteriological warfare is not a statement that people do not think about it ATOMIC ENERGY 245 Senator HA RT Well you do and you do not put it in a different category as a politicai matter looking forwr rd to the protection of the world Dr MORRISON I do put it in a very different category because it does not exist Senator HICKENLOOPER Would you care to answer my question of a little while ago now of a bomb set off 100 feet in the air Will it burn better than a bomb set off 1 500 feet in the air Dr MORRISON A little further away because at a given distance you are a little closer to the bomb In other words if you are right below the bomb and it is 1 000 feet above you are 1 000 feet away · enator HICKENLOOPER I understand that but I wondered if the radiation would be conducted along the air of whether it might be dissipated in the air Dr MORRISON I don't think so it might be The reflected heat from the ground might have a small initial effect but not serious Senator HICKENLQOPER It is all hot enough Dr MORRISON Yes sir In New Mexico where it did touch the ground the ground is covered with glass for about 1 000 feet Senator MILLIKIN Mr Chairman The CHAIRl iAN' Senator Millikin · Senator MILLIKIN What would be the effect if the bomb exploded in the ground in terms of radiation blast and heat Dr MORRISON If it exploded at or near the surface of the ground it would be very much the same as high in the air with the difference that the people would be closer to it and the difference that'the radioactive material would then probably be left on the ground in large amounts and perhaps with the other difference that the ground perhaps would be glazed and might be untenable for a very long time to come If you also wanted to include a situation where it was very far below the earth 50 or 100 or 500 feet below then it is clear that the situation would be very much changed here I don't like to go into detail but I would say this It would simply produce not an air blast but an ear h blast a ground shake There is no doubt but that it would · have great military importance I would rather not discuss it Senator MILLIKIN How would you protect rescue workers and other relief forces that necessarily would have to operate in an area where the bomb had explod d in the around · Dr MoRRISON I would keep them out Senator MILLIKIN Well there are essential functions in any large 0itY especially that have to keep going-rescue functions and utilities and things of that kind-that unless there was complete destruction unless there was a determination that this area be forever ab ndoned you have got to keep going · · I am curious as to how you would protect people that would have to work in the area as best they could Dr MORRISON I hope we don't have to face these problems I would say simply that I imagine they should run in and out quickly there would be a fringe where they could do that There would be another fringe wh re they might send volunteers to do dangerous things using tanks and there would be a central region which they could just abandon · 79879--46--pt 2-f' S 246 ATOMIC ENERGY Senator MILLIKIN Suppose they had to go in what sort of protective material would you clothe those people with · Dr MoRRISON Oh you would need 50 tons of lead Senator Mrr Lm IN Lead I don't want you to think I am fanatic on the subject of lead Senator HART Where is lead mined fLa 11ghti r 1 Senator MILLIKIN Coming from the West we are interested in those things I want to know about what might be used in a defensive way I quite agree with you that in most instances for these stationary objects for instance it would be cheaper to get insulation from other materials Then you could clos in the work with thicknesses of concrete or other materials but if you have moving objects people or appliances perhaps I take it that you will agree with me that lead and possibly other metals would make a good insulating material Dr MORRISON I do not want to give you the impression-it is quite wrong but it is very easy to do it-that it depends on the material There is really no specific material It depends on the weight of the material you use If you could dress a man in a suit weighing 50 tons of lead or any · other material I don't care what the material might be you could do that _ Senator MILLIKIN You can't practically do that You stated that you could surround it or him with a wall of concrete Dr MORRISON Yes or lead Senator MILLIKIN And of course there are many places where you could not surround even a stationary object that way You could not put a wall of concrete around it due to its placement From what • I have read it seems to me that you do have protection already for the articles of clothing like shoes and personal equipment of people who have to approach these radiation places that they may be clothed with protective material ' · Dr MoRRISON No that is really a misapprehension Senator if I may say so It is not possible to gain any worth-while protection by the amount of material that a man can carry on his own body It is not possible you just can't do it Senator HrcKENLOOPER That would depend on the degree of contamination Dr MORRISON But the point is that a man cannot carry enough protection he cannot i_ncrease his weight that much Also the time element enters into it how soon it is after the explosion · Senator HrcKENLOOPER It depends on whether you want to go into that area in 20 minutes or 2 days · · Dr MORRISON It depends on whether you want to go into it in 20 minutes or in 20 minutes and 10 seconds and most people would rather wait 10 seconds rather than carry the tons of lead they would need for protection Senator MILLIKIN It comes· from the degree of harmful radiation that remains does it not It loses its strength as time passes does it not Dr MORRISON Yes it does Senator MILLIKIN Therefore you have a decrease there in terms of time of radiation and perhaps some sort of protecti_ve material which ATOMIC ENERGY 247 might be utterly useless at the moment might be useful a week or two or 10 days from the explosion · Dr MoRRISON That is true but it is not true that anything that a man can carry around will give protection worthy of being called pi otection Senator MILLIKIN That depends entirely upon the problem of when you have to go into the area Sometimes you of necessity have to go into an area You are postulating that it would be better to stay out I suggest it might not be better to stay out I suggest that it might be essential to get in there Neither you nor I can sit here now and imagine the particular circumstance that will call for the decision but I do suggest that there might be a circumstance which will call for a decision Dr MORRISON This is quite true I am simplJ- saying that if he must get in there he will not get the protection with say 100 pounds of lead he can with 10 tons The additional amount say about 100 pounds that he can carry will not protect him sufficiently Senator MILLIKIN That again followE that you can theor etically coat a tank with lead Dr MORRISON Exactly Senator MILLIKIN And so there are circumstances and one 0£ them was lemonstrated by coating the tank with lead I am not mentioning lead except that I hq ve heard it mentioned in the press but it could be coated with some sort 0£ a protective material Dr MORRISON Yes but the protective material which' is worn on the body 0£ a man is not adequate against radiation The only reason that existed for oating the sho·es 0£ these men who walked in later and for their wearing special clothing was this It was simply clothing in the nature 0£ overalls so that they would not carry away on their person any 0£ the contaminating material It was not to give protection Y·ou can get protection from walls You must use walls and these walls will be much heavier than anything a man cil n carry He could not ca-fry enough to get a worth-while increase in protection Senator MILLIKIN Then you have a double problem You have the problem 0£ protecting the man himself against radiation and you also have the problem 0£ keeping him from carrying out the radiation is that right · Dr MORRISON That is right Senator MILLIKIN And in the latter instance _there is a definite need for some sort 0£ protective material to cover that·man Dr MORRISON That simply calls for clothing that he can wear and then throw away · Senator MILLIKIN Yes Dr MORRISON That is· all the protection you providt J there · The CHAIRMAN Doctor the bomb was dropped over Hiroshima at something 0£ a height That height I presume was chosen to get the greatest blast effect that could be gotten You have testified that many many people there were killed by the gamma rayR Would that result in a large deposit on the ground Dr MoRRISON It did not The CHAIRMAN It did not • 248 ATOMIC ENERGY Dr MORRISON It did not There was no physiological injury to any person in Hiroshima from material deposited on the ground We did not find any indication of that · The CHAIRJ11AN In other words the gamma rays went through the body and then were exhausted before they touched the ground is that the idea Dr MoRRISON Well the idea is this the gamma radiation is a ray Once it is emitted it is absorbed that is the end of it It is energy which turns into heat or chemical energy or something of that sort Therefore it will not last It is emitted and that is the end it is absorbed The things that last are the atoms of new elements which have the property of destroying themselves giving out radiations rays in the process · · · Now this is not true· when the bomb is exploded on ground But these bombs were exploded in the air and the radiation disappeared the gamma radiation moved through the area and was absorbed Senator HICKENLOOPER I have another question Doctor I would like to have your opinion ·on this question Do you think it reasonably possible-we know that it would be theoretically possible-do you think that it is reasonably possible that science will abandon the field of investigation into nuclear research• Do you think that there can be any law or any other force in the world that can prevent the investigations of science to the fullest possible extent in this new field · Dr MoRRISON ldo not think that it is in the tradition of science that this has ever been done Therefore to secure such a result is evidently a problem of extreme difficulty Senator HrnKENLOOPEJt Science has never abandoned a field of investigation once it has been opened up Dr MORRISON I think in recent years it is quite right in the last few hundred yea'rs it has never been done Senator MILLIKIN I mean in a field as successful as has been indicated here Dr MORRISON I don't know about the future I hope it will not I hope in the future they will bring forth new things in peace as they have done in war • Senator MILLIKIN Won't science and education keep searching for more and more light on this subject and more and mare knowledge Dr MoruusoN I believe that will be the case Senator MILLIKIN Isn't that almost inevitable I mean isn't that the human inevitability Dr MORRISON I think on this question you probably have mor experience than I · Senator MILLIKIN No I am not a scientist Dr MoRmsoN No but you are a man who knows how people act and organize themselves into states Senator MILLIKIN It se ems apparent to me that once th e is an area where scientists have discovered something profitable and opened up a further field of investigation that they will pursue that the investigation into natural laws It never has been abandoned that is no major field of investigation of that kind has ever been abandoned because of the ultimate purpose or the ultimate results • ATOMIC ENERGY 249 Dr MORRISON I believe that is true I am not saying that you cannot destroy investigation that it cannot be abandoned if you insis t upon it I am saying simply that it has never been done Senator· JOHNSON Mr Chairman The CnAIR IAN Senator J olmson Senator JOHNSON I should like to say to the witness to Mr Morrison that he is the most eloquent witness that I have ever heard since I have been around Congress I am sure that his power of description must be the envy of all reporters here present I know it is the envy of all the Senators here · I deem this pape-r that he has submitted to us a classic in direct statement and I shall preserve it and I shall use it He has made an almost unanswerable argument against TNT for one thing and I think he has made some arguments that no military man can escape-much as our military high command are trying to escape I· don't see how they are going to escape the argument he is making ·· ·• In listing the choices of death · he tells us that the victims of the bomb had a good many choices They might be killed by falling brick or they migHt be burned to death by the direct blast or they might be burned to death by secondary fires and if they escaped all of them the death ray would probably get them I want to ask him about the absence of oxygen caused by this tremendous blast and the wind that 1e has described the vacuums and all vVas it possible for persons to have suffocated for lack of oxygen and were secondary fires handicapped by a lack of oxygen in the immediate region Dr MORRISON I do not believe so Senator JOHNSON There is plenty of oxygen left after the wind has sucked them out Dr MORRISON You see after the blast has passed you £or 10 seconds then everything is back to normal again Presumably if you are still in one piece under all these other conditions you can presumably do without oxygen for 10 seconds You cannot do without your head for 10 seconds that is the trouble · Senator JOHNSON You cannot do without that at all but the interval of the absence of oxygen would be very small Dr MORRISON Very small Senator JOHNSON Ten seconds Dr MORRISON Much less but I said 10 seconds is evidently not serious I said that because I am sure of that figure I know it is much less by a £actor of a hundred or more Senator JOHNSON So suffocation was not one of the choices Dr MORRISON Except by having things £all on you and bury you which was not a very common cause The CHAIRMAN Doctor have you read General Arnold's report Dr MORRISON I have· The CHAIRMAN Did you by any chance read General Spaatz' story Dr MoRRISON I read that in the train coming to Washington sir and w s greatly impressed by i_t The CHAIRMAN Do you thrnk that that portrays what a future war would be 250 ATOMIC ENERGY Dr MoRRisoN I hope that it does not portray what the future circumstances of the world will be I believe it portrays correctly perhaps with a natural conservatism on the part of a general what a future war would be if engaged in by the J OWers Senator JoHNSON I have one more question Mr Chairman The CHAIRMAN Senator Johnson Senator JOHNSON I was intrigued by this statement I do not think you will soon see atomic automobiles though you may see atomic rockets and atomic power plan ts Now the atomic rocket is the thing I wanted to ask you about My understanding is that up to the present time this atomic energy that ' we have is either a tremendous explosion or else it exists in a minute sort of way In other words we either have a terrific explosion or the atoms split very casually one at a time and nothing happens Is there any way of controlling that explosion so that you can use it for a continuous flight of a rocket · Dr MORRISON I should like to answer that question but not in the most direct way you asked it I would i 10t like to say you could control the explosion because that is contradictory Before we could make a bomb we had to lean1 to produce a cont rolled nuclear react ion It was not a controlled explosion I don't know what a controlled explosion means but it was the release of energy at a uniform rate under conditions where it could be turned on and off In fact the gi·eat plant ·at Hanford is exactly this sort of thing Senator J_oHNSON But you cannot use the great pile at Hanford in a rocket bomb · Dr MoRRISON That is quite right but you can make smaller piles Senator JOHNSON Small enough to drive a rocket and still small • enough to be carried by a rocket '1 Dr MoRRisoN I believe so but I don't think I can go into any more detail Senator JOHNSON It looks to me as if it is the same question of lead pants Y OU were discussing with Senator Milliken a while ago that your pile would be so heavy that the rocket couldn't travel that the energy it produced would be less than its weight Dr MORRISON But who is riding on the rockets Senator If there are no people nearby no crew you do not need a very heavy shield The CHAIRMAN Senator isn't that perhaps getting into classified information Senator J'oHNSON I think that is as fantastic as Buck Rogers and I just wanted to challenge the witness on his statement here that we may see· atomic rockets I think that is a statement that ought to be challenged and I challenge it Dr MoRRISON I certainly will not engage in the manufacture of atomic rockets because I see no use· for them except in war but I think it is a natural development of the thing we have been working on and that such a thing could be produced · · · Senator MILLIKIN Mr Chairman I would like to ask the witness what he has done in the laboratory t o prepare atmosphere so that it may become highly inflammable The CHAIRMAN Isn't that classified It looks as though the chairman is getting security conscious ATOMIC ENERGY 251 Dr MoRRISON These matters were discussed by Dr Bethe yesterday I believe The CHAIRMAN Doctor you have thought a great deal about the future of our de fense I presume · Dr MoRRISON Yes The CHAIRMAN What relation has a 10 000 000-man army every one of them able to shoot the eye out of a squirrel at a thousand yards every one of them able to salute and come to attention and say Yes sir and No sir -what relation has that in your mind to ·the ability or the power compr essed in these bombs as a matter of defense Dr MoRRISON Do you really want me to answer that question The CHAIRMAN Yes I don't know why it shouldn't be answered It is something that I have thought about a good deal Dr MORRISON Well I can say these things · The CHAIRMAN Unless you think it is classified information Dr MoRRISON No I think it is controversial discussion on a subject · on which I have no special competence The CHAIRMAN I ask it of you on the theory that has be so often quoted 1P7 Clemenceau who said that war was too important to leav e to the generals with which I am in thorough accord Now on that basis as one amateur talking to another tell me what the relation is as you have thought about it Dr MORRISON I am still working for the War Department Laughter The CHAIRMAN Let the responsibility be mine Dr MORRISON Let me say that if you have as you will have in a future war 1 000 or 5 000 long-range rockets striking our industrial areas each one loaded with enough atomic explosive to destroy any city district th t is the central part of Washington lower Ma attan ·or any small city of three or four hundred thousand you will have an enormous installation which will perhaps intercept half of these or sevep-tenths of them or something of that sort but you will lose as I think has been said before something like one-third of your population in the first day of the war I do not know I do not like to think about prosecuting a war under these circumstances and that is why I want to stop there How the war would progress after that is a question I hope we will never have to answer It is clear to me that against such an attack a conventional army is of no value whether it is of no value in the further prosecution of the war is something I do not know about The CHAIRMAN I assume we have a navy in order to defend the country I was questioning myself last night and asked What good is a navy if you haven't got a country to defend · Dr MoRRISON You are going to always have a navy to defend Senator Laughter The CHAIRMAN I think I will let that one lie right where it is Has anyone else any questions Senator HICKENLOOPER Not unless you want to explore that field a little more It is a rather interesting field The CHAIRMAN It is I will let you go forward with it That last one stopped me Senator and in fact I think the whole argument was made in the one sentence 252 A'l OMIC ENERGY Senator HICKENLOOPER I am sorry Mr Chairman but I was engrossed in a maze of figures here so I missed the doctor's argument on· this number of men and so on I realize- that you are a physicist and not a professional soldier-Dr MORRISON Thank God Senator HICKENLOOPER But let us assume that the United States or any country elected to use the atomic bomb having a sufficient stock of them for either offense or defense Roughly if you have any opinion about how many people do you think we would need efficiently trained to use that weapon successfully either in offense or defense DI' MORRISON I am not quite sure how you successfully use it in defense Senator HICKENLOOPER I realize that the fellow who hits first has a tremendous advantage in this thing Let us suppose that we are going to use the bomb and want to use it efficiently that is to kill the most people and do the most damage to our enemy · Dr MORRISON Well let me try to make a ITTless I have not thought about this question and it is useful to think about only to sl ow how expensive the whole proposition will be I hope These bombs will cost as Dr Oppenheimer said a couple of timesand I may quote him without any violation of security-in the order of $1 000 000 apiece I think to launch them in some fancy nd complicated missilel like a super V-2 would probably not be practical unless the V-'2 itself cost only 10 times as much as the bomb as in the case of the airplane · in relation to its bomb load Let us say it cost $10 000 000 to launch an atomic missle Now if you have to do this in the number of thousands and were spending around 10 or '20 billion dollars you probably have an equal sum for all the administrative and commumcation problems so that you will spend in the order of $50 000 000 000 You can transfer that into the number o f people who have to be employed in the enterprise as well as I Senator HrcKENLOOPER Could you give an opinion on this Could we successfully conduct an atomic war just using some very rough figures now with say a well-trained military land force-let's leave the Navy out of it-of a million men as easily as we could with a trained force of 10 million men on land · Dr MORRISON I really do not know I would prefer not to discuss those questions • Senator HrcrrE OOPER Well my point is as to whether or not 10 000 000 foot soldiers would contribute anything more to the launching of an atomic attack than 1 000 000 foot soldiers for instance or whether the 9 000 000 would be surplus Dr MoRRISON I think not one foot soldier will contribute to the launching of an attack but there are other things to do I do not want to discuss what other things may be done · · I think that you can see what our point of view is namely that to launch an atomic attack you need people to press buttons and make· instruments What else you need is not my province to dismiss Senator HrcKENLOOPER In other words I was trying to develop the point whether you believe marching armies would contribute very ATOMIC ENERGY 253 much to the effecti veness of 'the atomic bomb from our standpoint or whether it is purely or almost exclusively a scientific and engineering problem confining itself to the construction of the materials and the launching of the ships-with the trained personnel of course Dr MoRRISON I think that the impact of war will be so great in the first day that I 'do not know what will happen thereafter Senator RussELL Mr Chairman I regret I was a bit late I wonder if the doctor has discussed the range of these rockets and these missiles and whether he thinks there is any limitation on the distances that they can traverse with accuracy Dr MORRISON I know nothing about rockets or missiles from my own experience If the Germans were able to make a rocket under their conditions that will travel 300 miles and hit within a couple of miles if they were able to do that under circumstances in which they cQuld not develop weapons like we were able to develop such as the atomic bomb I do not doubt that 10 times this range and equal accuracy is attainable I do not know of my own experience but it seems to me common sense that progress in this rl nge will b made There is certainly no new physical fact involved but detailed engineering study General Spaatz and General Arnold have spoken about these things and must have received information that these things are practical I myself see nothing against them The CHAIR i IAN Are there any further questions Thank you very much Dr Morrison Senator MILLIKIN I would like to add my appreciation to that of Senator Johnson of the very graphic and informative descriptions you gave us of the conditions at Hiroshima The CHAIRMAN Dr Goudsmit STATEMENT OF DR S A GOUDSMIT PROFESSOR OF PHYSICS UNIVERSITY OF MICHIGAN The CHAIRMAN Dr Goudsmit have you a prepared statement Dr GounsMIT I have no prepared statement with me but I may have one later I wish to point out first of all that my connection with the atomic bomb is quite different from that of th previous witnesses I have not worked on the project at all except in intelligence functions I was connected with the War Department mission which was sent overseas in order to find out what the German progress was along the project of the atomic bomb and that was what we have done and that is the information which I can give you Also because of that function I may have a few suggestions which might be useful even though they are one-sided suggestions as to control and supervision In spite of certain preliminary newspaper reports we can say that the Germans did not have anything at all They were way behind They just did not have the vision which the Allied scientists had I believe I have put down a few points about the German progress The German scientists had abandoned the hope of making a bomb during this war entirely They used the idea of the bomb to sell it to the Government and to the military officials