,worlds ,)9 ,worlds3                    
,! ,/ory ( ,nucle> ,en]gy               
,volume #c              ,nucle> ,fission
  ,nucle> ,fusion  ,beyond ,fusion      
by ,isaac ,asimov                       
,unit$ ,/ates ,atomic ,en]gy ,commission
                       ,(fice (         
,in=mation ,s]vices                     
,libr>y ( ,congress ,catalog ,c>d ,numb]
 #ge-ahidgg                             
#aigb    ,no?+ 9 ! hi/ory ( mank9d has  
op5$ our eyes to !  possibilities (     
sci5ce z has ! developm5t ( atomic p[]4 
,9 !  la/ #bjj ye>s1 p h se5 ! com+ ( ! 
/eam eng9e1 !  /eamboat1 ! railroad     
locomotive1 ! automobile1 ! airplane1   
radio1  motion pictures1 television1 !  
ma*9e age 9 g5]al4 ,yet none ( x  seem$ 
q s fanta/ic1 q s unbelievable1 z :at   
man has done  s9ce #aici ) ! atom 444   
!re seem to be almo/ no limits to :at   
may lie ahead3 inexhau/ible en]gy1 new  
worlds1 ev]-wid5+ k  ( ! physical       
univ]se4                                
,isaac ,asimov                          

,illu/ration3 ,photograph ( night sky   
,nucle> en]gy is play+ a vital role 9 ! 
life ( e man1 woman1  & *ild 9 ! ,unit$ 
,/ates today4 ,9 ! ye>s ahead x w affect
  increas+ly all ! peoples ( ! e>?4 ,x  
is ess5tial t all  ,am]icans ga9 an     
und]/&+ ( ?is vital =ce if !y are to    
dis*>ge ?\ghtfully _! responsibilities z
 citiz5s & if !y  are to realize fully !
 myriad b5efits t nucle> en]gy (f]s  !m4
    ,! ,unit$ ,/ates ,atomic ,en]gy     
,commission provides ?is booklet to help
  y a*ieve su* und]/&+4                 
,,unit$ ,,/ates ,,atomic ,,en]gy        
,,commission      ,dr4 ,james ,r4       
,s*les+]1 ,*airman    ,james ,t4 ,ramey 
,dr4 ,cl>5ce ,e4 ,l>son    ,william ,o4 
,d\b    ,dr4 ,dixy ,lee ,ray            
,illu/ration3 ,isaac ,asimov            
,,isaac ,,asimov receiv$ 8 academic     
degrees f ,columbia ,univ]sity &  is    
,associate ,pr(essor ( ,bio*emi/ry at ! 
,bo/on ,univ]sity ,s*ool  ( ,m$ic9e4 ,he
 is a prolific au?or :o has writt5 ov]  
#ajj books 9  ! pa/ #ah ye>s1 includ+   

ab\t #bj sci5ce fiction works1 & books  
= *ildr54 ,8 _m excell5t sci5ce books = 
! public cov]  subjects 9 ma!matics1    
physics1 a/ronomy1 *emi/ry1 & biology1  
su* z ,! ,g5etic ,code1 ,inside ! ,atom1
 ,build+ ,blocks ( !  ,univ]se1 ,und]/&+
 ,physics1 ,! ,new ,intellig5t ,man's   
,guide to  ,sci5ce1 & ,asimov's         
,biographical ,encyclop$ia ( ,sci5ce &  
,te*nology4 ,9 #aife ,dr4 ,asimov       
receiv$ ! ,james ,t4 ,grady ,aw>d ( !   
,am]ican ,*emical ,society = 8 major    
contribution 9 report+  sci5ce progress 
to ! public4                            
,illu/ration3 ,photograph ( night sky   
,,cont5ts                               
,,volume #a    ,introduction            
#e    ,atomic ,weights                  
#f    ,electricity                      
#aa        ,units ( ,electricity        
#aa        ,ca?ode ,rays                
#ac        ,radioactivity               
#ag        ,! ,/ructure ( ! ,atom       
#be        ,atomic ,numb]s              
#cj        ,isotopes                    

#ce    ,en]gy                           
#dg        ,! ,law ( ,cons]vation (     
,en]gy                                  
#dg        ,*emical ,en]gy              
#ej        ,electrons & ,en]gy          
#ed        ,! ,en]gy ( ! ,sun           
#ee        ,! ,en]gy ( ,radioactivity   
#eg                                     
,,volume #b    ,mass & ,en]gy           
#fi    ,! ,/ructure ( ! ,nucleus        
#ge        ,! ,proton                   
#ge        ,! ,proton-,electron ,!ory   
#gf        ,protons 9 ,nuclei           
#hj        ,nucle> ,bomb>dm5t           
#hb        ,p>ticle ,accel]ators        
#hf    ,! ,neutron                      
#ib        ,nucle> ,sp9                 
#ib        ,discov]y ( ! ,neutron       
#ie        ,! ,proton-,neutron ,!ory    
#ih        ,! ,nucle> ,int]action       
#aja        ,neutron ,bomb>dm5t         
#ajg                                    
,,volume #c    ,nucle> ,fission         
#aag        ,new ,elem5ts               
#aag        ,! ,discov]y ( ,fission     

#abb        ,! ,nucle> ,*a9 ,reaction   
#abg        ,! ,nucle> ,bomb            
#aca        ,nucle> ,reactors           
#ada    ,nucle> ,fusion                 
#adf        ,! ,en]gy ( ! ,sun          
#adf        ,!rmonucle> ,bombs          
#adh        ,controll$ ,fusion          
#aej    ,beyond ,fusion                 
#aeh        ,antimatt]                  
#aeh        ,! ,unkn[n                  
#afc    ,read+ ,li/                     
#afe    ,illu/ration3 ,enrico ,f]mi     
7left7 & ,niels ,bohr discuss physics z 
!y /roll along ! ,appian ,way outside   
,rome 9 #aica4                          
,,nucle> ,,fission      ,new ,elem5ts   
,9 #aicd ,enrico ,f]mi began 8 fir/     
exp]im5ts involv+ !  bomb>dm5t ( uranium
 ) neutrons--exp]im5ts t 7 to *ange !   
face ( ! _w4    ,f]mi _h f\nd t sl[     
neutrons1 :i* _h v little en]gy1 7      
easily absorb$ by atomic nuclei--m      
easily ?an fa/ neutrons 7  absorb$1 &   
c]ta9ly m easily ?an *>g$ p>ticles 74   
,(t5 :at happ5$ 0 t ! neutron 0 simply  

absorb$ by !  nucleus4 ,s9ce ! neutron  
has a mass numb] ( #a & an atomic numb] 
( #j 7because x is un*>g$71 a nucleus t 
absorbs a neutron rema9s  an isotope ( !
 same elem5t1 b increases its mass      
numb]4    ,= in/ance1 suppose t neutrons
 are us$ to bomb>d hydrog5-#a1  :i* !n  
captures "o ( ! neutrons4 ,f a s+le     
proton1 x w  become a proton plus a     
neutron2 f hydrog5-#a1 x w become       
hydrog5-#b4 ,a new nucleus =m$ 9 ?is way
 w be at a high] en]gy  & t en]gy is    
emitt$ 9 ! =m ( a gamma ray4            
,sometimes ! m massive isotope t is =m$ 
?r\gh neutron  absorption is /able1 z   
hydrog5-#b is4 ,sometimes x is n1 b is  
radioactive in/ead4 ,because x has add$ 
a neutron1 x has too _m  neutrons =     
/ability4 ,! be/ way ( adju/+ ! matt] is
 to emit  a beta p>ticle 7electron74    
,?is conv]ts "o ( ! neutrons into a     
proton4 ,! mass numb] /ays ! same b !   
atomic numb] increases  by "o4    ,!    
elem5t rhodium1 = example1 :i* has an   
atomic numb] ( #de1 has  only #a /able  

isotope1 ) a mass numb] ( #ajc4 ,if     
rhodium-#ajc 7#de  protons1 #eh         
neutrons7 absorbs a neutron1 x becomes  
rhodium-#ajd 7#de  protons1 #ei         
neutrons71 :i* is n /able4 ,rhodium-#ajd
 emits a beta  p>ticle1 *ang+ a neutron 
to a proton s t ! nucle> comb9ation     
becomes #df protons & #eh neutrons4 ,?is
 is palladium-#ajd1 :i* is  /able4      
,illu/ration3 ,f]mi's laboratory 9 ,rome
 9 #aicj4    ,z ano!r example1          
indium-#aae 7#di protons1 #ff neutrons7 
absorbs a  neutron & becomes indium-#aaf
 7#di protons1 #fg neutrons71 :i* gives 
(f a beta p>ticle & becomes t9-#aaf 7#ej
 protons1 #ff neutrons71 :i*  is /able4 
,!re are ov] #ajj isotopes t w absorb   
neutrons & end by  becom+ an isotope (  
an elem5t "o high] 9 ! atomic numb]     
scale4  ,f]mi obs]v$ a numb] ( ^! cases4
    ,hav+ done s1 he 0 b\nd to ask :at  
w\ld happ5 if uranium 7  bomb>d$ )      
neutrons4 ,w\ld its isotopes also be    
rais$ 9 atomic  numb]--9 ?is case f #ib 
to #ic8 ,if t 7 s x w\ld be v  excit+1 =

 uranium _h ! highe/ atomic numb] 9 !   
entire scale4  ,nobody _h ev] discov]$  
any sample ( elem5t numb] #ic1 b p]haps 
x c\ld be =m$ 9 ! laboratory4    ,9     
#aicd1 !re=e1 ,f]mi bomb>d$ uranium )   
neutrons 9 ! hope (  obta9+ atoms (     
elem5t #ic4 ,neutrons 7 absorb$ & :atev]
 0  =m$ did give (f beta p>ticles1 s    
elem5t #ic %\ld be !re4  ,h[ev]1 f\r    
diff]5t k9ds ( beta p>ticles 7diff]5t 9 
_!  en]gy cont5t7 7 giv5 (f & ! matt]   
grew v confus+4 ,f]mi  c\ld n def9itely 
id5tify ! pres5ce ( atoms ( elem5t #ic &
  nei!r c\ld anyone else = sev]al ye>s4 
,o!r ?+s turn$ up1  h[ev]1 :i* 7 ev5 m  
significant4    ,be=e go+ on to ^! o!r  
?+s1 h[ev]1 x %\ld be m5tion$  t        
und\bt$ly elem5t #ic 0 =m$ ev5 ?\gh     
,f]mi c\ldn't  cle>ly demon/rate ! fact4
 ,9 #aici ! ,am]ican physici/s ,edw9    
,mattison ,mc,millan 7#aijg-    7 &     
,philip ,hauge ,abelson 7#aiac-    71   
aft] bomb>d+ uranium atoms ) sl[        
neutrons1 7 able to id5tify  elem5t #ic4
 ,s9ce uranium _h orig9ally be5 nam$ = !

 planet1  ,uranus1 ! new elem5t beyond  
uranium 0 ev5tually nam$ = !  planet    
,neptune1 :i* lay beyond ,uranus4       
,elem5t #ic is !re=e call$  8neptunium04
    ,illu/ration3 ,lise ,meitn]         
,illu/ration3 ,emilio ,segr             
,illu/ration3 ,edw9 ,m4 ,mc,millan      
,illu/ration3 ,otto ,r4 ,fris*          
,illu/ration3 ,gl5n ,t4 ,seaborg        
,illu/ration3 ,philip ,h4 ,abelson      
,:at happ5$ 0 exactly :at 0 expect$4    
,uranium-#bch 7#ib protons1  #adf       
neutrons7 add$ a neutron to become      
uranium-#bci 7#ib protons1 #adg         
neutrons71 :i* emitt$ a beta p>ticle to 
become neptunium-#bci 7#ic  protons1    
#adf neutrons74    ,9 fact1             
neptunium-#bci also emitt$ a beta       
p>ticle s x ought to  become an isotope 
( an elem5t ev5 high] 9 ! atomic numb]  
scale4  ,?is "o1 elem5t #id1 0 nam$     
8plutonium0 aft] ,pluto1 ! planet       
beyond ,neptune4 ,! isotope1            
plutonium-#bci1 =m$ f neptunium-#bci1  0
 only feebly radioactive1 h[ev]1 & x 0 n

 cle>ly id5tifi$  until #aida4    ,!    
actual discov]y ( ! elem5t plutonium    
came ! ye> be=e1  h[ev]1 :5             
neptunium-#bch 0 =m$4 ,x emitt$ a beta  
p>ticle &  became plutonium-#bch1 an    
isotope t 0 radioactive en\gh to be     
easily detect$ & id5tifi$ by ,gl5n      
,!odore ,seaborg 7#aiab-    71  & 8     
co-work]s1 :o complet$ ,mc,millan's     
exp]im5ts :5 he 0  call$ away to o!r    
def5se rese>*4    ,neptunium & plutonium
 7 ! fir/ 8transuranium elem5ts0 to be  
produc$ 9 ! laboratory1 b !y w]5't !    
la/4 ,ov] ! next #cj  ye>s1 isotopes 7  
=m$ t conta9$ m & m protons 9 !  nucleus
 & !re=e _h high] & high] atomic numb]s4
 ,at !  mom5t ( writ+1 isotopes ( e     
elem5t up to & includ+ elem5t  #aje h   
be5 =m$4    ,a numb] ( ^! new elem5ts h 
be5 nam$ = "s ( !  sci5ti/s important 9 
! hi/ory ( nucle> rese>*4 ,elem5t #if is
  8curium01 nam$ = ,pi]re & ,m>ie       
,curie2 elem5t #ii is 8e9/e9ium0  =     
,alb]t ,e9/e92 & elem5t #ajj is 8f]mium0
 = ,enrico ,f]mi4    ,elem5t #aja is    

8m5delevium0 = ! ,russian *emi/ ,dmitri 
,m5delev1  :o e>ly 9 #ahfi 0 ! fir/ to  
arrange ! elem5ts 9 a reasonable  &     
useful ord]4 ,elem5t #ajc is 8lawr5cium0
 = ,erne/ ,o4 ,lawr5ce4  8,ru!r=dium0 = 
,erne/ ,ru!r=d has be5 propos$ = elem5t 
#ajd4    ,& 8hahnium0 = ,otto ,hahn     
7#ahgi-aifh71 a ,g]man physical *emi/ ^:
  contribution we w come to %ortly1 has 
be5 propos$ = elem5t #aje4              
,neptunium1 h[ev]1 0 n ! fir/ new elem5t
 to be creat$ 9 !  laboratory4 ,9 ! e>ly
 #aicjs1 !re 7 /ill #b elem5ts ) fairly 
l[ atomic numb]s t _h nev] be5 discov]$4
 ,^! 7 !  elem5ts ) atomic numb]s #dc & 
#fa4    ,9 #aicg1 ?\gh1 molybd5um       
7atomic numb] #db7 _h be5 bomb>d$ )     
neutrons 9 ,lawr5ce's laboratory 9 !    
,unit$ ,/ates4 ,x might conta9  small   
quantities ( elem5t #dc z a result4 ,!  
,italian physici/ ,emilio  ,segr 7#aije-
    71 :o _h work$ ) ,f]mi1 obta9$ a    
sample ( !  bomb>d$ molybd5um & inde$   
obta9$ indications ( ! pres5ce (  elem5t
 #dc4 ,x 0 ! fir/ new elem5t to be      

manufactur$ by  artificial means & 0    
call$ 8te*netium0 f ! ,greek ^w =       
8artificial04    ,! te*netium isotope t 
0 =m$ 0 radioactive4 ,inde$1 all !      
te*netium isotopes are radioactive4     
,elem5t #fa1 discov]$ 9 #aide &  nam$   
8prome?ium01 also has no /able isotopes4
 ,te*netium &  prome?ium are ! only     
elem5ts ) atomic numb]s less ?an #hd t  
d n h ev5 a s+le /able isotope4      ,! 
,discov]y ( ,fission    ,b let u get    
back to ! bomb>dm5t ( uranium ) neutrons
 rese>*  t ,f]mi _h begun4 ,aft] he _h  
report$ 8 "w1 o!r physici/s  repeat$ x &
 also got a v>iety ( beta p>ticles & 7  
also  unable to decide :at 0 go+ on4    
,illu/ration3 ,lise ,meitn] & ,otto     
,hahn 9 _! laboratory 9 !  #aicjs4      
,"o way to tackle ! problem 0 to add to 
! sy/em "s /able  elem5t t 0 *emically  
simil> to ! t9y traces ( radioactive    
isotopes t might be produc$ ?r\gh !     
bomb>dm5t ( uranium4  ,aft]w>ds ! /able 
elem5t c\ld probably be sep>at$ out ( ! 
mixture & ! trace ( radioactivity w\ld1 

x 0 hop$1 be c>ri$  along ) x4 ,! /able 
elem5t w\ld be a 8c>ri]04    ,among ^?  
work+ on ! problem 7 ,otto ,hahn & 8    
,au/rian  co-work]1 ! physici/ ,lise    
,meitn] 7#ahgh-aifh74 ,among ! pot5tial 
c>ri]s !y add$ to ! sy/em 0 ! elem5t1   
b>ium1 :i* has an  atomic numb] ( #ef4  
,!y f\nd t a consid]able quantity ( !   
radioactivity did inde$ accompany !     
b>ium :5 !y sep>at$ t  elem5t out ( !   
sy/em4    ,a natural conclusion 0 t !   
isotopes produc+ ! radioactivity        
belong$ to an elem5t t 0 *emically v    
simil> to b>ium4  ,suspicion fell at    
once on radium 7atomic numb] #hh71 :i* 0
 v l  b>ium inde$ z f> z *emical        
prop]ties 7 conc]n$4    ,lise ,meitn]1  
:o 0 ,jewi%1 f\nd x difficult to "w 9   
,g]many1  h[ev]1 = x 0 !n "u ! rule ( ! 
/rongly anti-,semitic  ,nazi regime4 ,9 
,m>* #aich ,g]many occupi$ ,au/ria1 :i* 
became "p  ( ! ,g]man realm4 ,meitn] 0  
no long] protect$ by h] ,au/rian        
citiz5%ip & _h to flee ! c\ntry & g to  
,/ockholm1 ,sw$54  ,hahn rema9$ 9       

,g]many & cont9u$ work+ on ! problem ) !
  ,g]man physical *emi/ ,fritz ,/rassman
 7#aijb-    74    ,al?\gh ! suppos$     
radium1 :i* possess$ ! radioactivity1 0 
v l b>ium 9 *emical prop]ties1 ! two 7 n
 entirely  id5tical4 ,!re 7 ways (      
sep>at+ !m1 & ,hahn & ,/rassman  busi$  
!mselves 9 try+ to accompli% ?is 9 ord] 
to isolate !  radioactive isotopes1     
conc5trate !m1 & /udy !m 9 detail4 ,ov] 
& ov] aga91 h[ev]1 !y fail$ to sep>ate !
 b>ium & !  suppos$ radium4    ,sl[ly1 x
 began to seem to ,hahn t ! failure to  
sep>ate ! b>ium  & ! radioactivity meant
 t ! isotopes to :i* ! radioactivity    
belong$ _h to be s mu* l b>ium z to be  
no?+ else b  b>ium4 ,he hesitat$ to say 
s1 h[ev]1 because x seem$ unbelievable4 
,if ! radioactive isotopes includ$      
radium1 t 0 conceivable4  ,radium _h an 
atomic numb] ( #hh1 only f\r less ?an   
uranium's #ib4 ,y  c\ld imag9e t a      
neutron be+ absorb$ by a uranium nucleus
 might  make ! latt] s un/able z to     
cause x to emit #b alpha p>ticles &     

become radium4 ,b>ium1 h[ev]1 _h an     
atomic numb] ( #ef1 only a  little ov]  
half t ( uranium4 ,h[ c\ld a uranium    
nucleus be made to  turn into a b>ium   
nucleus unless x m or less broke 9 half8
 ,no?+  l t _h ev] be5 obs]v$ be=e &    
,hahn hesitat$ to sugge/  x4    ,:ile he
 0 n]v+ himself to d s1 h[ev]1 ,lise    
,meitn]1 9  ,/ockholm1 receiv+ reports (
 :at 0 be+ done 9 ,hahn's laboratory  & 
?9k+ ab\t x1 decid$ t unhe>d-( or n1 !re
 0 only  "o explanation4 ,! uranium     
nucleus 0 break+ 9 half4    ,actually1  
:5 "o /opp$ to ?9k ( x 7aft] gett+ ov] !
  initial %ock7 x wasn't s unbelievable 
at t4 ,! nucle> =ce is  s %ort-range1 x 
b>ely rea*es f end to end ( a l>ge      
nucleus  l t ( uranium4 ,left to itself1
 x holds toge!r mo/ ( !  "t1 b ) ! add$ 
en]gy ( an ent]+ neutron1 we might      
imag9e  %ock waves go+ ?r\gh x & turn+ !
 nucleus into some?+ l  a quiv]+ drop ( 
liquid4 ,sometimes ! uranium nucleus    
recov]s1  keeps ! neutron1 & !n goes on 
to beta-p>ticle emission4 ,&  sometimes 

! nucleus /ret*es to ! po9t :]e ! nucle>
 =ce  doesn't q hold x toge!r4 ,x       
becomes a dumbbell %ape & !n !          
electromagnetic repulsion ( ! two halves
 7bo? positively *>g$7  breaks x ap>t   
altoge!r4    ,x doesn't break into equal
 halves4 ,nor does x always break at    
exactly  ! same place1 s t !re 7 a numb]
 ( diff]5t fragm5ts  possible 7:i* 0 :y 
!re 0 s mu* confusion74 ,/ill1 "o ( !  m
 common ways 9 :i* x might break w\ld be
 into b>ium &  krypton4 7,_! respective 
atomic numb]s1 #ef & #cf1 w\ld add up to
  #ib47    ,meitn] & h] nephew1 ,otto   
,rob]t ,fris* 7#aijd-    71 :o 0 9      
,cop5hag51 ,d5m>k1 prep>$ a pap] sugge/+
 t ?is 0 :at 0  happ5+4 ,x 0 publi%$ 9  
,janu>y #aici4 ,fris* pass$ x on to !   
,dani% physici/ ,niels ,bohr            
7#ahhe-aifb7 ) :om he 0 work+4 ,!       
,am]ican biologi/ ,william ,ar*ibald    
,arnold 7#aijd-    71 :o 0 also  work+ 9
 ,cop5hag5 at ! "t1 sugge/$ t ! splitt+ 
( !  uranium nucleus into halves be     
call$ 8fission01 ! t]m us$ = !          

division-9-two ( liv+ cells4 ,! "n /uck4
    ,9 ,janu>y #aici1 j ab\t ! "t       
,meitn] & ,fris*'s pap] 0  publi%$1     
,bohr _h arriv$ 9 ! ,unit$ ,/ates to    
att5d a conf]5ce  ( physici/s4 ,he c>ri$
 ! news ( fission ) him4 ,! o!r         
physici/s att5d+ ! conf]5ce he>d ! news 
& 9 a high /ate  ( excitem5t at once set
 ab\t /udy+ ! problem4 ,)9 a matt] (    
weeks1 ! fact ( uranium fission 0       
confirm$ ov] & ov]4    ,"o /rik+ fact   
ab\t uranium fission 0 ! l>ge am\nt (   
en]gy  x releas$4 ,9 g5]al1 :5 a v      
massive nucleus is conv]t$ to a  less   
massive "o1 en]gy is releas$ because ( !
 *ange 9 ! mass  defect1 z ,a/on _h %[n 
9 ! #aibjs4 ,:5 ! uranium nucleus breaks
  d[n ?r\gh ! ord9>y radioactive        
processes to become a less massive  lead
 nucleus1 en]gy is giv5 (f accord+ly4   
,:51 h[ev]1 x breaks  9 two to become ! 
mu* less massive nuclei ( b>ium &       
krypton 7or  o!rs 9 t neighborhood7 mu* 
m en]gy is giv5 (f4    ,x quickly turn$ 
out t uranium fission gave (f some?+ l  

t5  times z mu* nucle> en]gy p] nucleus 
?an did any o!r nucle>  reaction kn[n at
 ! "t4    ,ev5 s1 ! quantity ( en]gy    
releas$ by uranium fission 0 only a  t9y
 fraction ( ! en]gy t w5t into !        
prep>ation ( !  neutrons us$ to br+ ab\t
 ! fission1 if ea* neutron t /ruck a    
uranium atom br\ght ab\t a s+le fission 
( t #a atom4    ,"u ^? conditions1      
,ru!r=d's suspicion t mank9d w\ld nev]  
be able to tap nucle> en]gy probably    
/ill rema9$ true4 7,he _h be5  dead = #b
 ye>s at ! "t ( ! discov]y ( fission47  
,h[ev]1 ^? 7 n ! conditions4      ,!    
,nucle> ,*a9 ,reaction    ,e>li] 9 ?is  
hi/ory1 we discuss$ *a9 reactions       
involv+ *emical  en]gy4 ,a small bit (  
en]gy c ignite a *emical reaction t w\ld
  produce m ?an en\gh en]gy to ignite a 
neighbor+ section ( !  sy/em1 :i* w\ld 9
 turn produce /ill m--& s on1 & s on4 ,9
  ?is way ! flame ( a s+le mat* c\ld />t
 a fire 9 a leaf t  w\ld burn d[n an    
entire =e/1 & ! en]gy giv5 (f by !      
burn+ =e/ w\ld be enorm\sly high] ?an ! 

initial en]gy ( !  mat* flame4    ,might
 !re n be su* a ?+ z a 8nucle> *a9      
reaction08 ,c\ld "o  initiate a nucle>  
reaction t w\ld produce some?+ t w\ld   
initiate m ( ! same t w\ld produce      
some?+ t w\ld  initiate /ill m ( ! same 
& s on8    ,9 t case1 a nucle> reaction1
 once />t$1 w\ld cont9ue ( its  own     
accord1 & 9 return = ! trifl+ inve/m5t t
 w\ld s]ve  to />t x--a s+le neutron1   
p]haps--a va/ am\nt ( breakd[ns w\ld    
result ) ! deliv]y ( a va/ am\nt (      
en]gy4 ,ev5 if x 7  necess>y to exp5d q 
a bit ( en]gy to produce ! #a neutron t 
w\ld />t ! *a9 reaction1 "o w\ld end )  
an enorm\s pr(it4    ,:at's m1 s9ce !   
nucle> reaction w\ld spread f nucleus to
  nucleus ) million?s-(-a-second        
int]vals1 !re w\ld be1 9 a v  brief "t1 
s _m nuclei break+ d[n t !re w\ld be a  
va/  explosion4 ,! explosion 0 sure to  
be millions ( times z p[]ful z  ord9>y  
*emical explosions involv+ ! same       
quantity ( explod+  mat]ial1 s9ce !     
latt] us$ only ! electromagnetic        

int]action1  :ile ! =m] us$ ! mu* /rong]
 nucle> int]action4    ,! fir/ to ?9k   
s]i\sly ( su* a nucle> *a9 reaction 0 ! 
,hung>ian physici/ ,leo ,szil>d         
7#ahih-aifd74 ,he 0 work+ 9 ,g]many  9  
#aicc :5 ,adolf ,hitl] came to p[] &1   
s9ce he 0 ,jewi%1 he  felt x w\ld be    
wise to leave ,g]many4 ,he w5t to ,great
 ,brita9 &  !re1 9 #aicd1 he consid]$   
c]ta9 new types ( nucle> reactions  t _h
 be5 discov]$4    ,9 ^!1 x sometimes    
happ5$ t a fa/ neutron might /rike a    
nucleus ) suffici5t en]gy to cause x to 
emit #b neutrons4 ,9 t  way ! nucleus1  
absorb+ #a neutron & emitt+ #b1 w\ld    
become a  light] isotope ( ! same       
elem5t4    ,b :at w\ld happ5 if ea* ( ! 
#b neutrons t em]g$ f !  orig9al t>get  
nucleus /ruck new nuclei & =c$ !        
emission ( a  pair ( neutrons f ea*4    
,!re w\ld n[ be a total ( #d neutrons   
fly+ ab\t & if ea* /ruck new nuclei !re 
w\ld next be #h  neutrons & s on4 ,f !  
initial inve/m5t ( a s+le neutron  !re  
might soon be c\ntless billions initiat+

 nucle> reactions4    ,szil>d1 fe>+ !   
inevitability ( w> & fe>+ fur!r t !     
brutal lead]s ( ,g]many might seek & use
 su* a nucle> *a9  reaction z a weapon 9
 w>f>e1 secretly appli$ = a pat5t on a  
device int5d+ to make use ( su* a nucle>
 *a9 reaction4 ,he hop$  to turn x ov]  
to ! ,briti% ,gov]nm5t1 :i* might !n use
 its  possession z a way ( re/ra9+ !    
,nazis & keep+ ! peace4    ,h[ev]1 x    
w\ldn't h work$4 ,x took ! impact ( a v 
en]getic  neutron to br+ ab\t ! emission
 ( #b neutrons4 ,! neutrons t  !n em]g$ 
f ! nucleus simply didn't h en\gh en]gy 
to keep  ?+s go+4 7,x 0 l try+ to make  
wet wood cat* fire47    ,b :at ab\t     
uranium fission8 ,uranium fission 0     
initiat$ by sl[  neutrons4 ,:at if      
uranium fission also produc$ neutrons z 
well z  be+ initiat$ by a neutron8 ,w\ld
 n ! neutrons produc$ s]ve to  initiate 
new fissions t w\ld produce new neutrons
 & s on  endlessly8    ,x seem$ v likely
 t fission produc$ neutrons & inde$1    
,f]mi1  at ! conf]5ce :]e fission 0 fir/

 discuss$1 sugge/$ x at  once4 ,massive 
nuclei possess$ m neutrons p] proton ?an
 less  massive ones did4 ,if a massive  
nucleus 0 brok5 up into #b consid]ably  
less massive ones1 !re w\ld be a surplus
 ( neutrons4 ,suppose1 =  in/ance1      
uranium-#bch broke d[n into b>ium-#ach &
 krypton-#hf4  ,b>ium-#ach conta9s #hb  
neutrons & krypton-#hf #ej neutrons = a 
total  ( #acb4 ,! uranium-#bch nucleus1 
h[ev]1 conta9s #adf neutrons4    ,!     
uranium fission process 0 /udi$ at once 
to see if neutrons 7  actually giv5 (f &
 a numb] ( diff]5t physici/s1 includ+   
,szil>d1 f\nd t !y 74    ,n[ ,szil>d 0  
fac$ ) a nucle> *a9 reaction he 0 c]ta9 
w\ld  "w4 ,only sl[ neutrons 7 involv$ &
 ! individual nucle>  breakd[ns 7 f> m  
en]getic ?an any?+ else t _h yet be5    
discov]$4 ,if a *a9 reaction c\ld be    
/>t$ 9 a sizable piece (  uranium1      
unimag9able quantities ( en]gy w\ld be  
produc$4 ,j #a  gram ( uranium1 und]go+ 
complete fission1 w\ld deliv] ! en]gy   
d]iv$ f ! total burn+ ( #c tons ( coal &

 w\ld deliv] t  en]gy 9 a t9y fraction (
 a second4    ,szil>d1 :o _h come to !  
,unit$ ,/ates 9 #aicg1 cle>ly visualiz$ 
! trem5d\s explosive =ce ( some?+ t w\ld
 h to be call$  a 8nucle> bomb04 ,szil>d
 dread$ ! possibility t ,hitl] might    
obta9 ! use ( su* a bomb ?r\gh ! ag5cy (
 ,g]many's nucle>  sci5ti/s4    ,p>tly  
?r\gh ,szil>d's ef=ts1 physici/s 9 !    
,unit$ ,/ates & 9  o!r ,we/]n nations   
oppos$ to ,hitl] began a program (      
volunt>y  secrecy 9 #aidj1 to avoid     
pass+ along any h9ts to ,g]many4 ,:at's 
m1 ,szil>d enli/$ ! s]vices ( two o!r   
,hung>ian refugees1 !  physici/s ,eug5e 
,paul ,wign] 7#aijb-    7 & ,edw>d      
,tell] 7#aijh-    7  & all approa*$     
,e9/e91 :o _h also fl$ ,g]many & come to
  ,am]ica4    ,illu/ration3 ,leo ,szil>d
    ,illu/ration3 ,eug5e ,p4 ,wign]     
,e9/e9 0 ! mo/ pre/igi\s sci5ti/ !n liv+
 & x 0  ?\ght a lett] f him to !        
,presid5t ( ! ,unit$ ,/ates w\ld be  mo/
 p]suasive4 ,e9/e9 sign$ su* a lett]1   
:i* expla9$ !  possibility ( a nucle>   

bomb & urg$ t ! ,unit$ ,/ates n all[  a 
pot5tial enemy to come into possession (
 x fir/4    ,l>gely z a result ( ?is    
lett]1 a huge rese>* team 0 put  toge!r 
9 ! ,unit$ ,/ates1 to :i* o!r ,we/]n    
nations also  contribut$1 ) b "o aim--to
 develop ! nucle> bomb4      ,! ,nucle> 
,bomb    ,al?\gh ! !ory ( ! nucle> bomb 
seem$ cle> & simple1 a great  _m        
practical difficulties /ood 9 ! way4 ,9 
! fir/ place1 if  only uranium atoms    
und]w5t fission a supply ( uranium _h at
 lea/ to  be obta9$ 9 pure =m1 = if !   
neutrons /ruck nuclei ( elem5ts  o!r ?an
 uranium1 !y w\ld simply be absorb$ &   
remov$ f !  sy/em1 end+ ! possibility ( 
a *a9 reaction4 ,?is alone 0 a  heavy   
task1 s9ce !re _h be5 s little use =    
uranium 9 quantity  t !re 0 almo/ no    
supply 9 exi/5ce & no exp]i5ce 9 h[ to  
purify x4    ,secondly1 ! supply (      
uranium might h to be a l>ge "o1 =      
neutrons didn't necess>ily ent] ! fir/  
uranium atom !y  approa*$4 ,!y mov$ ab\t
 "h & !re1 mak+ glanc+ collisions1  &   

travell+ q a di/ance1 p]haps1 be=e /rik+
 head-on &  ent]+ a nucleus4 ,if 9 t "t 
!y _h pass$ outside ! lump (  uranium1  
!y 7 useless4    ,illu/ration3 ,frankl9 
,d4 ,roosevelt      ,alb]t ,e9/e9       
,old ,grove ,rd4    ,nassau ,po9t       
,peconic1 ,long ,isl&      ,augu/ #bnd1 
#aici      ,f4,d4 ,roosevelt1           
,presid5t ( ! ,unit$ ,/ates1    ,:ite   
,h\se    ,wa%+ton1 ,d4,c4    ,sir3      
,"s rec5t "w by ,e4 ,f]mi & ,l4 ,szil>d1
 :i* has be5 communicat$  to me 9       
manuscript1 leads me to expect t !      
elem5t uranium may be  turn$ into a new 
& important s\rce ( en]gy 9 ! imm$iate  
future4 ,c]ta9 aspects ( ! situation :i*
 has aris5 seem to call  = wat*fulness  
&1 if necess>y1 quick action on ! "p ( !
  ,adm9i/ration4 ,i believe !re=e t x is
 my duty to br+ to y\r  att5tion !      
foll[+ facts & recomm5dations3    ,9 !  
c\rse ( ! la/ f\r mon?s x has be5 made  
probable--?r\gh  ! "w ( ,joliot 9       
,france z well z ,f]mi & ,szil>d 9      
,am]ica--t x may become possible to set 

up a nucle> *a9 reaction  9 a l>ge mass 
( uranium1 by :i* va/ am\nts ( p[] &    
l>ge  quantities ( new radium-l elem5ts 
w\ld be g5]at$4 ,n[ x  appe>s almo/     
c]ta9 t ?is c\ld be a*iev$ 9 ! imm$iate 
future4    ,?is new ph5om5on w\ld also  
lead to ! con/ruction ( bombs1 & x  is  
conceivable--?\gh mu* less c]ta9--t     
extremely p[]ful bombs (  a new type may
 ?us be con/ruct$4 ,a s+le bomb ( ?is   
type1 c>ri$  by boat & explod$ 9 a port1
 might v well de/roy ! :ole port  toge!r
 ) "s ( ! surr\nd+ t]ritory4 ,h[ev]1 su*
 bombs  might v well prove to be too    
heavy = transportation by air4          
,illu/ration3 ,alb]t ,e9/e9      ,!     
,unit$ ,/ates has only v poor ores (    
uranium 9 mod]ate    quantities4 ,!re is
 "s good ore 9 ,canada & ! =m]          
,cze*oslovakia1 :ile ! mo/ important    
s\rce ( uranium is ,belgian    ,congo4  
,9 view ( ?is situation y may ?9k x     
desirable to h "s    p]man5t contact    
ma9ta9$ betwe5 ! ,adm9i/ration & ! gr\p 
( physici/s work+ on *a9 reactions 9    

,am]ica4 ,"o possible way    ( a*iev+   
?is might be = y to entru/ ) ?is task a 
p]son    :o has y\r confid5ce & :o c\ld 
p]haps s]ve 9 an in(ficial    capacity4 
,8 task might comprise ! foll[+3      a7
 to approa* ,gov]nm5t ,dep>tm5ts1 keep  
!m in=m$ ( !    fur!r developm5t1 & put 
=w>d recomm5dations = ,gov]nm5t         
action1 giv+ p>ticul> att5tion to !     
problem ( secur+ a    supply ( uranium  
ore = ! ,unit$ ,/ates2      b7 to spe$  
up ! exp]im5tal "w1 :i* is at pres5t be+
    c>ri$ on )9 ! limits ( ! budgets (  
,univ]sity    laboratories1 by provid+  
funds1 if su* funds be requir$1 ?r\gh   
8 contacts ) private p]sons :o are will+
 to make    contributions = ?is cause1 &
 p]haps also by obta9+ !    co-op]ation 
( indu/rial laboratories :i* h !        
necess>y    equipm5t4      ,i und]/& t  
,g]many has actually /opp$ ! sale (     
uranium    f ! ,cze*oslovakian m9es :i* 
%e has tak5 ov]4 ,t %e    %\ld h tak5   
su* e>ly action might p]haps be und]/ood
 on !    gr\nd t ! son ( ! ,g]man       

,"u-,secret>y ( ,/ate1 von    ,weizsck]1
 is atta*$ to ! ,kais]-,wilhelm-,in/itut
 9 ,b]l9 :]e    "s ( ! ,am]ican "w on   
uranium is n[ be+ repeat$4      ,y\rs v 
truly1                                  
,illu/ration3 _/sign$_/    7,alb]t      
,e9/e97    ,z ! quantity ( uranium )9   
:i* ! fission *a9 reaction 0  initiat$  
grew l>g]1 m & m ( ! neutrons produc$   
f\nd a  m>k & ! fission reaction w\ld   
die out m & m sl[ly4  ,f9ally1 at "s    
p>ticul> size--! 8critical size0--!     
fission  reaction did n die at all1 b   
ma9ta9$ itself1 ) en\gh ( !  neutrons   
produc$ f9d+ _! m>k to keep ! nucle>    
reaction  proce$+ at a /eady rate4 ,at  
any great] size ! nucle> reaction  w\ld 
accel]ate & !re w\ld be an explosion4   
,x wasn't ev5 necess>y to s5d neutrons  
into ! uranium to />t !  process4 ,9    
#aida ! ,russian physici/ ,georgii      
,nikolaevi* ,fl]ov  7#aiac-    7 f\nd t 
e once 9 a :ile a uranium atom w\ld     
und]go fission )\t ! introduction ( a   
neutron4 ,occasionally !  r&om quiv]+ ( 

a nucleus w\ld br+ ab\t a %ape t !      
nucle>  int]action c\ld n br+ back to   
normal & ! nucleus w\ld !n  break ap>t4 
,9 a gram ( ord9>y uranium1 !re is a    
nucleus  und]go+ su* 8spontane\s        
fission0 e #b m9utes on ! av]age4       
,!re=e1 en\gh uranium ne$ only be br\ght
 toge!r to surpass  critical size & x w 
explode )9 seconds1 = ! fir/ nucleus  t 
und]goes spontane\s fission w />t ! *a9 
reaction4    ,fir/ e/imates made x seem 
t ! quantity ( uranium ne$$ to  rea*    
critical size 0 extraord9>ily great4    
,fully #ii4c ( ! metal  is uranium-#bch1
 h[ev]1 &1 z soon z fission 0 discov]$1 
,bohr  po9t$ out t !re 7 !oretical      
reasons = suppos+ t x  0 ! uranium-#bce 
isotope 7mak+ up only #j4g ( ! :ole7 t 0
  ! "o und]go+ fission4 ,inve/igation   
prov$ him "r4 ,inde$1 !  uranium-#bch   
nucleus t5d$ to absorb sl[ neutrons )\t 
fission1 &  to g on to beta-p>ticle     
production t =m$ isotopes ( neptunium  &
 plutonium4 ,9 ?is way uranium-#bch     
actually int]f]$ ) !  *a9 reaction4     

,9 any quantity ( uranium1 ! m          
uranium-#bce pres5t & ! less            
uranium-#bch1 ! m easily ! *a9 reaction 
w\ld proce$ & !  l[] ! critical size    
ne$$4 ,va/ ef=ts 7 !re=e made to        
sep>ate ! #b isotopes & prep>e uranium )
 a high] ?an normal  conc5tration (     
uranium-#bce 78enri*$ uranium074    ,(  
c\rse1 !re 0 no great desire = a fe>ful 
explosion to get out  ( h& :ile ! *a9   
reaction 0 be+ /udi$4 ,be=e any bomb    
c\ld be con/ruct$1 ! me*anism ( ! *a9   
reaction w\ld h to  be /udi$4 ,c\ld a   
*a9 reaction capable ( produc+ en]gy 7= 
useful purposes z well z = bombs7 be    
e/abli%$8 ,to te/ ?is1 a  quantity (    
uranium 0 ga!r$ 9 ! hope t a controll$  
*a9  reaction ( uranium fission c\ld be 
e/abli%$4 ,= t purpose1  control rods ( 
a sub/ance t w\ld easily absorb neutrons
 & sl[  ! *a9 reaction 7 us$4 ,! metal1 
cadmium1 s]v$ admirably =  ?is purpose4 
,!n1 too1 ! neutrons releas$ by fission 
7 pretty en]getic4 ,!y  t5d$ to travel  
too f> too soon & get outside ! lump (  

uranium  too easily4 ,to produce a *a9  
reaction t c\ld be /udi$ ) "s  safety1 !
 pres5ce ( a mod]ator 0 ne$$4 ,?is 0 a  
supply (  small nuclei t did n absorb   
neutrons readily1 b absorb$ "s (  !     
en]gy ( collision & sl[$ d[n any neutron
 t /ruck x4  ,nuclei su* z hydrog5-#b1  
b]yllium-#i1 or c>bon-#ab 7 useful      
mod]ators4 ,:5 ! neutrons produc$ by    
fission 7 sl[$1 !y  travell$ a small]   
di/ance be=e be+ absorb$ 9 _! turn & !  
critical size w\ld aga9 be r$uc$4       
,t[>d ! end ( #aidb ! initial /age ( !  
project rea*$ a  climax4 ,blocks (      
graphite conta9+ uranium metal & uranium
 oxide  7 pil$ up 9 huge quantities     
7enri*$ uranium 0 n yet  available7 9   
ord] to approa* critical size4 ,?is took
 place "u !  /&s ( a football /adium at 
! ,univ]sity ( ,*icago1 ) ,enrico  ,f]mi
 7:o _h come to ! ,unit$ ,/ates 9 #aich7
 9 *>ge4#a    ,! l>ge /ructure 0 call$  
an 8atomic pile0 at fir/ because ( !    
blocks ( graphite be+ pil$ up4 ,! prop] 
"n = su* a device1  & ! "o t 0 ev5tually

 adopt$1 01 h[ev]1 8nucle>  reactor04   
,on ,decemb] #b1 #aidb1 calculations %[$
 t ! nucle> reactor 0  l>ge en\gh to h  
rea*$ critical size4 ,! only ?+ prev5t+ 
! *a9 reaction f su/a9+ itself 0 !      
cadmium rods t 7  ins]t$ "h & !re 9 !   
pile & t 7 soak+ up neutrons4           
,illu/ration3 ,cutaway model ( ! ,we/   
,/&s ( ,/agg ,field %[+  ! fir/ pile 9 !
 squa% c\rt b5ea? x4    ,illu/ration3 ,!
 ext]ior ( ! build+4    ,illu/ration3   
,graphite lay]s =m ! base ( ! pile1     
left4 ,on !  "r is ! sev5? lay] (       
graphite & edges ( ! six? lay]  conta9+ 
#c-;in* pseudosph]es ( black uranium    
oxide4 ,beg9n+ )  lay] #f1 alt]nate     
c\rses ( graphite conta9+ uranium metal 
&_/or  uranium oxide fuel 7 sep>at$ by  
lay]s ( solid graphite blocks4          
,illu/ration3 ,t5? lay] ( graphite      
blocks conta9+ pseudosph]es  ( black &  
br[n uranium oxide4 ,! br[n briquets1   
slightly ri*] 9  uranium1 7 conc5trat$ 9
 ! c5tral area4 ,on ! "r is !  n9ete5?  
lay] ( graphite cov]+ lay] #ah conta9+  

slugs (  uranium oxide4    ,"o by "o !  
cadmium rods 7 pull$ out4 ,! numb] (    
uranium atoms  und]go+ fission ea*      
second rose &1 f9ally1 at #c3de p4m41 ! 
uranium fission became self-su/a9+4 ,x  
kept go+ on its own 7)  ! cadmium rods  
ready to be pu%$ 9 if x look$ z ?\gh x 7
  gett+ out ( h&--some?+ calculations   
%[$ 0 n likely74    ,news ( ?is success 
0 ann\nc$ to ,wa%+ton by a cauti\s      
telephone  call f ,ar?ur ,holly ,compton
 7#ahib-aifb7 to ,james ,bryant ,conant 
7#ahic-    74 8,! ,italian navigator has
 l&$ 9 ! new _w01 said  ,compton4       
,conant ask$1 8,h[ 7 ! natives801 & !   
answ] 01  8,v fri5dly04    ,?is 0 ! day 
& mom5t :5 ! _w ent]$ ! 8nucle> age04   
,= ! fir/ "t1 mank9d _h con/ruct$ a     
device 9 :i* !  nucle> en]gy be+ giv5 (f
 0 great] ?an ! en]gy p\r$ 94  ,mank9d  
_h tapp$ ! res]voirs ( nucle> en]gy &   
c\ld put x to  use4 ,_h ,ru!r=d liv$ b  
#f m ye>s1 he w\ld h se5 h[ wrong  he 0 
to ?9k x c\ld nev] be done4    ,! p (   
e>? rema9$ unaw>e ( :at _h tak5 place 9 

,*icago  & physici/s cont9u$ to "w t[>d 
! developm5t ( ! nucle>  bomb4          
,enri*$ uranium 0 successfully prep>$4  
,critical sizes 7 br\ght  l[ en\gh to   
make a nucle> bomb small en\gh to be    
c>ri$ by plane to  "s t>get4 ,suppose "o
 _h #b slabs ( enri*$ uranium1 ea* bel[ 
critical size1 b :i* 7 above critical   
size if comb9$4 ,&  suppose an explosive
 device 7 add$ t1 at "s desir$ mom5t1   
c\ld be set (f 9 su* a way t x w\ld     
drive #a slab ( enri*$  uranium aga9/ ! 
o!r4 ,!re w\ld be an in/ant explosion ( 
deva/at+ p[]4 ,or suppose ! enri*$      
uranium 7 arrang$ 9  loosely pack$      
pieces to beg9 ) s t ! fly+ neutrons 7 9
  op5 air too (t5 to ma9ta9 ! *a9       
reaction4 ,a prop]ly arrang$  explosion 
might compress ! uranium into a d5se    
ball4 ,neutron  absorption w\ld become m
 effici5t & aga91 an explosion w\ld     
foll[4    ,illu/ration3 ,nucle> ,fission
 ( ,uranium3 ,a neutron hits ! nucleus  
( an atom ( uranium4 ,! neutron splits !
 nucleus into two p>ts &  creates huge  

am\nts ( en]gy 9 ! =m ( heat4 ,at ! same
 "t  o!r neutrons are releas$ f !       
splitt+ nucleus & ^!  cont9ue ! fission 
process 9 a *a9 reaction4    ,on ,july  
#af1 #aide1 a device t w\ld result 9 a  
nucle> explosion 0  set up ne>          
,alamogordo1 ,new ,mexico1 ) n]v\s      
physici/s wat*+  f a safe di/ance4 ,x   
work$ p]fectly2 ! explosion 0 trem5d\s4 
,by t "t ,nazi ,g]many _h be5 defeat$1 b
 ,japan 0 /ill  fight+4 ,two m devices 7
 prep>$4 ,aft] a w>n+1 "o 0  explod$ ov]
 ! ,japanese city ( ,hiro%ima on ,augu/ 
#f1 #aide1 & !  o!r ov] ,nagasaki #b    
days lat]4 ,! ,japanese gov]nm5t        
surr5d]$  & ,_w ,w> ,,ii came to an end4
    ,x 0 ) ! bla/ ov] ,hiro%ima t ! _w  
came to "k x 0  9 ! nucle> age & t !    
f]oci\s weapon ( ! nucle> bomb  exi/$4  
7,! popul> "n = x at ! "t 0 8atomic     
bomb0 or  8,a-bomb047    ,dur+ ! w>1    
,g]man sci5ti/s may h be5 try+ to       
develop a  nucle> bomb1 b1 if s1 !y _h n
 yet succe$$ at ! "t ,g]many  met its   
f9al defeat4 ,soviet physici/s1 "u ,igor

 ,vasilievi*  ,kur*atov 7#aijc-aifj71 7 
also work+ on ! problem4 ,! dislocation 
( ! w>1 :i* inflict$ mu* m damage on !  
,soviet ,union ?an on  ! ,unit$ ,/ates1 
kept ! ,soviet ef=t f succe$+ :ile x 0  
on4 ,h[ev]1 s9ce ! ,soviets 7 among !   
victors1 !y 7 able to  cont9ue aft] !   
w>4    ,9 #aidi ! ,soviets explod$ _!   
fir/ nucle> bomb4 ,9 #aieb !  ,briti%   
did ! same2 9 #aifj1 ! ,fr5*2 & 9 #aifd1
 ! ,*9ese4    ,al?\gh _m nucle> bombs h 
be5 explod$ = te/ purposes1 !  two ov]  
,hiro%ima & ,nagasaki h be5 ! only ones 
us$ 9 "t (  w>4    ,nor ne$ nucle> bombs
 be consid]$ z hav+ de/ructive pot5tial 
only4 ,!re is ! possibility t1 ) prop]  
precautions1 !y might  be us$ to make   
excavations1 bla/ out h>bors or canals1 
break up  und]gr\nd rock =mations to    
recov] oil or o!r res\rces1 & 9  o!r    
ways d ! "w ( *emical explosives ) f>   
great] spe$ &  economy4 ,x has ev5 be5  
sugge/$ t a s]ies ( nucle> bomb         
explosions might be us$ to hurl space   
vehicles =w>d 9 voyages away  f e>?4    

,nucle> ,reactors    ,! developm5t ( !  
nucle> *a9 reaction 0 n 9 ! direction  (
 bombs only4 ,nucle> reactors design$ = 
! controll$ production  ( useful en]gy  
multipli$ 9 numb] & 9 effici5cy s9ce    
,f]mi's  fir/ 8pile04 ,_m nations n[    
possess !m1 & !y are us$ = a  v>iety (  
purposes4#b    ,illu/ration3 ,! ,,uss   
,nautilus1 ! _w's fir/ nucle> p[]$      
subm>9e1 9 ,new ,york h>bor4    ,9 #aied
 ! fir/ nucle> subm>9e ! ,,uss ,nautilus
 0 laun*$ by  ! ,unit$ ,/ates4 ,its p[] 
0 obta9$ entirely f a nucle>  reactor1 &
 x 0 n necess>y = x to rise to ! surface
 at %ort  int]vals 9 ord] to re*>ge its 
batt]ies4 ,nucle> subm>9es h  cross$ !  
,arctic ,ocean "u ! ice cov]1 & h       
circumnavigat$  ! globe )\t surfac+4    
,9 #aiei bo? ! ,soviet ,union & ! ,unit$
 ,/ates laun*$  nucle>-p[]$ surface     
vessels4 ,! ,soviet %ip 0 ! icebreak]1  
,l591 & ! ,am]ican %ip 0 a m]*ant       
vessel1 ! ,,ns ,savannah4    ,9 ! #aiejs
 nucle> reactors 7 also us$ z ! s\rce ( 
p[] =  ! production ( electricity =     

civilian use4 ,! ,soviet ,union built a 
small /ation ( ?is sort 9 #aied1 :i* _h 
a capacity ( #e1jjj  kil[atts4 ,!       
,briti% built "o ( #ib1jjj kil[att      
capacity1 :i* !y  call$ ,cald] ,hall4 ,!
 fir/ ,am]ican nucle> reactor = civilian
 use  began op]ation at ,%ipp+port1     
,p5nsylvania1 9 #aieh4 ,x 0 ! fir/      
really full-scale civilian nucle> p[]   
plant 9 ! _w4    ,! _w appe>$ to h f>   
great] s\rces ( en]gy ?an _h be5        
expect$4 ,! 8fossil fuels0--coal1 oil & 
natural gas--7 be+ us$  at su* a rate t 
_m speculat$ t ! gas & oil w\ld be gone 
9 decades & ! coal 9 c5turies4 ,0 x     
possible t uranium might  n[ s]ve z a   
new s\rce t w\ld la/ indef9itely8    ,x 
0 r disappo9t+ t x 0 uranium-#bce :i*   
und]w5t  fission1 because t isotope made
 up only #j4g ( ! uranium t  exi/$4 ,if 
uranium-#bce 7 all we _h & all we ev]   
c\ld h1 !  en]gy supply ( ! _w w\ld /ill
 be r too limit$4    ,!re 7 o!r possible
 8nucle> fuels01 h[ev]4 ,!re 0          
plutonium-#bci1 :i* w\ld also fission "u

 neutron bomb>dm5t4 ,x  _h an ord9>y    
half-life 7= a radioactive *ange 9 :i* x
 gave (f  alpha p>ticles7 ( #bd1cjj     
ye>s1 :i* is long en\gh to make x easy  
to h&le4    ,b h[ c plutonium-#bci be   
=m$ 9 suffici5t quantities to be        
useful8 ,aft] all1 x doesn't occur 9    
nature4 ,surpris+ly1 t turn$  out to be 
easy4 ,uranium-#bch atoms w absorb _m ( 
! neutrons t  are con/antly leak+ out ( 
! reactor & w become fir/               
neptunium-#bci & !n plutonium-#bci4 ,!  
plutonium1 be+ a diff]5t  elem5t f !    
uranium1 c be sep>at$ f uranium & obta9$
 9  useful quantities4    ,su* a device 
is call$ a 8bre$] reactor0 because x    
bre$s fuel4  ,inde$1 x c be s design$ to
 produce m plutonium-#bci ?an !         
uranium-#bce x uses up1 s t y actually  
end up ) m nucle>  fuel ?an y />t$ )4 ,9
 ?is way1 all ! uranium on e>? 7&  n j  
uranium-#bce7 c be consid]$ pot5tial    
nucle> fuel4    ,illu/ration3 ,!        
,%ipp+port ,atomic ,p[] ,/ation1 ! fir/ 
full-scale1 nucle>-electric /ation built

 exclusively = civilian  ne$s1 provides 
electricity = ! homes & factories ( !   
great]  ,pittsburgh area4 ,!            
pressuriz$-wat] reactor1 :i* n[ has a   
#ij1jjj-net-electrical-kil[att capacity1
 began comm]cial op]ation 9  #aieg4 ,!  
reactor is 9 ! l>ge build+ 9 ! c5t]4    
,illu/ration3 ,! lights ( d[nt[n        
,pittsburgh4    ,! fir/ bre$] reactor 0 
complet$ at ,arco1 ,idaho1 9 ,augu/     
#aiea1  & on ,decemb] #bj produc$ ! v   
fir/ electricity on e>? to come  f      
nucle> p[]4 ,nev]!less1 bre$] reactors =
 comm]cial use  are /ill a matt] = !    
future4#c    ,ano!r isotope capable (   
fission+ "u neutron bomb>dm5t is        
uranium-#bcc4 ,x does n occur 9 nature1 
b 0 =m$ 9 !  laboratory by ,seaborg &   
o!rs 9 #aidb4 ,x has a half-life (      
#afb1jjj  ye>s4 ,x c be =m$ f naturally 
occurr+ ?orium-#bcb4  ,?orium-#bcb w    
absorb a neutron to become ?orium-#bcc4 
,!n #b beta  p>ticles are giv5 (f s t ! 
?orium-#bcc becomes fir/                
protact9ium-#bcc & !n uranium-#bcc4     

,if a ?orium %ell surr\nds a nucle>     
reactor1 fissionable uranium-#bcc  is   
=m$ )9 x & is easily sep>at$ f ! ?orium4
 ,9 ?is  way1 ?orium is also add$ to !  
li/ ( e>?'s pot5tial nucle>  fuels4#d   
,if all ! uranium & ?orium 9 ! e>?'s    
cru/ 7includ+ ! ?9  scatt]+ ( ^? elem5ts
 ?r\gh granite1 = in/ance7 7  available 
= use1 we might get up to #ajj times z  
mu* en]gy f x  z f all ! coal & oil on !
 planet4 ,un=tunately1 x is v  unlikely 
t we w ev] be able to make use ( all !  
uranium &  ?orium4 ,x is widely & ?9ly  
spread ?r\gh ! cru/al rocks &  mu* ( x  
c\ld n be extract$ )\t us+ up m en]gy   
?an  w\ld be suppli$ by x once isolat$4 
,ano!r problem re/s ) ! nature ( !      
fission reaction4 ,:5 !  uranium-#bce   
nucleus 7or plutonium-#bci or           
uranium-#bcc7 und]goes fission1  x      
breaks up into any ( a l>ge numb] (     
middle-siz$ nuclei t are                
radioactive--mu* m int5sely radioactive 
?an ! orig9al fuel4 7,x  0 f among ^!   
8fission products0 t isotopes ( elem5t  

#fa 7  fir/ obta9$ 9 #aide4 ,com+ f !   
nucle> fire1 x rem9d$ its  discov]]s (  
,prome!us1 :o /ole fire f ! sun 9 !     
,greek  my?s1 & s x 0 call$             
8prome?ium047    ,! fission products    
/ill conta9 en]gy & "s ( !m c be us$  9 
lightweight 8nucle> batt]ies04 ,su*     
nucle> batt]ies 7 fir/  built 9 #aied4  
,"s batt]ies1 us+ plutonium-#bch r ?an  
fission  products1 h be5 put to use 9   
p[]+ artificial satellites ov]  long    
p]iods4    ,un=tunately1 only a small   
proportion ( ! fission products c be    
put to pr(itable use4 ,mo/ mu/ be       
dispos$ (4 ,!y are dang]\s  because !   
radiations !y give (f are deadly & _c be
 detect$  by ! ord9>y s5ses4 ,!y are v  
difficult to dispose ( safely1  & !y mu/
 n be all[$ to get into ! environm5t1   
especially  s9ce "s ( !m rema9 dang]\s =
 decades or ev5 c5turies4               
,illu/ration3 ,! ,exp]im5tal ,bre$]     
,reactor ,no4 #b build+ complex  9      
,idaho4 ,! reactor is 9 ! dome-%ap$     
/ructure4                               

,,nucle> ,,fusion      ,! ,en]gy ( !    
,sun    ,z x happ5s1 ?\gh1 nucle>       
fission is n ! only r\te to useful      
nucle> en]gy4    ,a/on's /udies 9 !     
#aibjs _h %[n t x 0 ! middle-siz$       
nuclei t 7 mo/ tightly pack$4 ,en]gy    
w\ld be giv5 (f if  middle-siz$ nuclei 7
 produc$ f ei!r extreme4 ,n only w\ld   
en]gy be =m$ by ! breakup ( p>ticul>ly  
massive nuclei ?r\gh  fission1 b also   
?r\gh ! comb9ation ( small nuclei to =m 
l>g]  ones 78nucle> fusion074    ,9     
fact1 f ,a/on's /udies x c\ld be se5 t1 
mass = mass1  nucle> fusion w\ld produce
 f> m en]gy ?an nucle> fission4 ,?is  0 
p>ticul>ly true 9 ! conv]sion ( hydrog5 
to helium2 t is1  ! conv]sion ( !       
individual protons ( #d sep>ate hydrog5 
nuclei  into ! #b-proton--#b-neutron    
/ructure ( ! helium nucleus4 ,a gram (  
hydrog51 und]go+ fusion to helium1 w\ld 
deliv] "s fifte5 times  z mu* en]gy z a 
gram ( uranium und]go+ fission4    ,z   
e>ly z #aibj1 ! ,engli% a/ronom] ,ar?ur 
,/anley ,edd+ton  7#ahhb-aidd7 _h       

speculat$ t ! sun's en]gy might be d]iv$
 f  ! int]action ( subatomic p>ticles4  
,"s sort ( nucle> reaction  seem$1 by   
!n1 to be ! mo/ reasonable way ( acc\nt+
 = !  va/ en]gies con/antly be+ produc$ 
by ! sun4    ,! speculation became m    
plausible ) ea* ye>4 ,edd+ton himself   
/udi$ ! /ructure ( />s1 & by #aibf _h   
produc$ conv9c+  !oretical reasons =    
suppos+ t ! c5t] ( ! sun 0 at  enorm\s  
d5sities & temp]atures4 ,a temp]ature ( 
"s #ae1jjj1jjj to  #bj1jjj1jjj;,c seem$ 
to *>act]ize ! sun's c5t]4    ,at su*   
temp]atures1 atoms c\ld n exi/ 9 e>?ly  
fa%ion4 ,held  toge!r by ! sun's /rong  
gravitational field1 !y collid$ )  su*  
en]gy t all or almo/ all _! electrons 7 
/ripp$ (f1  & little m ?an b>e nuclei 7 
left4 ,^! b>e nuclei c\ld  approa* ea*  
o!r mu* m closely ?an :ole atoms c\ld   
7:i* 0  :y ! c5t] ( ! sun 0 s mu* m d5se
 ?an e>?ly matt]  c\ld be74 ,! b>e      
nuclei1 sma%+ toge!r at c5tral-sun      
temp]atures1 c\ld cl+ toge!r & =m m     
complex nuclei4 ,nucle>  reactions      

br\ght ab\t by su* int5se heat 7millions
 ( degrees7 are  call$ 8!rmonucle>      
reactions04    ,z ! #aibjs progress$    
fur!r /udies ( ! *emical /ructure ( !   
sun %[$ x to be ev5 ri*] 9 hydrog5 ?an  
_h be5 ?\ght4 ,9  #aibi ! ,am]ican      
a/ronom] ,h5ry ,norris ,russell         
7#ahgg-aieg7 report$  evid5ce t ! sun 0 
#fj hydrog5 9 volume4 7,ev5 ?is 0 too   
cons]vative2 #hj is consid]$ m ne>ly    
correct n[47 ,if ! sun's  en]gy 7 bas$  
on nucle> reactions at all1 !n x _h to  
be !  result ( hydrog5 fusion4 ,no?+    
else 0 pres5t 9 suffici5t  quantity to  
be useful z a fuel4    ,m & m 0 le>n$   
ab\t ! exact mann] 9 :i* nuclei         
int]act$ & ab\t ! quantity ( en]gy giv5 
(f 9 p>ticul>  nucle> reactions4 ,x     
became possible to calculate :at might  
be go+  on inside ! sun by consid]+ !   
d5sities & temp]atures pres5t1  ! k9d & 
numb] ( diff]5t nuclei available1 & !   
quantity (  en]gy t mu/ be produc$4 ,9  
#aich ! ,g]man-,am]ican physici/ ,hans  
,albre*t ,be! 7#aijf-    7 & ! ,g]man   

a/ronom] ,c>l ,fri$ri* von  ,weizsck]   
7#aiab-    7 indep5d5tly work$ out !    
possible reactions1  & hydrog5 fusion 0 
%[n to be a ?or\ghly practical way (    
keep+ ! sun go+4    ,?anks to ! high    
rate ( en]gy production by !rmonucle>   
reactions  & to ! va/ quantity ( hydrog5
 9 ! sun1 n only has x be5  possible = !
 sun to h be5 radiat+ en]gy = ! la/     
#e1jjj1jjj1jjj ye>s or s1 b x w cont9ue 
to radiate en]gy 9 !  pres5t fa%ion = at
 lea/ #e1jjj1jjj1jjj ye>s into ! future4
    ,illu/ration3 ,hans ,be!    ,ev5 s1 
! %e] quantity ( :at is go+ on 9 ! sun  
is /agg]+  9 e>?ly t]ms4 ,9 ! sun       
#fej1jjj1jjj tons ( hydrog5 are conv]t$ 
into helium e second1 & 9 ! process ea* 
second sees !  disappe>ance ( #d1fjj1jjj
 tons ( mass4      ,!rmonucle> ,bombs   
,c\ld !rmonucle> reactions be made to   
take place on e>?8 ,!  conditions t exi/
 9 ! c5t] ( ! sun w\ld be extremely     
difficult to duplicate on ! e>?1 s !re 0
 a natural se>* =  any k9d ( nucle>     
fusion t w\ld produce simil> en]gies to 

^?  go+ on 9 ! sun b :i* w\ld be easi]  
to br+ ab\t4    ,!re are #c hydrog5     
isotopes kn[n to exi/4 ,ord9>y hydrog5  
is  almo/ entirely hydrog5-#a1 ) a      
nucleus made up ( a s+le proton4  ,small
 quantities ( hydrog5-#b 7deut]ium7 ) a 
nucleus made up ( a  proton plus a      
neutron also exi/ & su* atoms are       
p]fectly /able4    ,9 #aicd ,ru!r=d1    
along ) ! ,au/ralian physici/ ,m>cus    
,laur5ce  ,elw9 ,oliphant 7#aija-    7 &
 ! ,au/rian *emi/ ,paul ,h>teck  7#aijb-
    7 s5t hydrog5-#b nuclei fly+ into   
hydrog5-#b t>gets &  =m$ hydrog5-#c     
7also call$ 8tritium0 f ! ,greek ^w =   
8?ird07 ) a nucleus made up ( a proton  
plus #b neutrons4 ,hydrog5-#c  is mildly
 radioactive4    ,hydrog5-#b fuses to   
helium m easily ?an hydrog5-#a does &1  
all  ?+s be+ equal1 hydrog5-#b w d s at 
l[] temp]atures ?an  hydrog5-#a4        
,hydrog5-#c requires l[] temp]atures    
/ill4 ,b ev5 =  hydrog5-#c x /ill takes 
millions ( degrees4    ,hydrog5-#c1     
al?\gh ! easie/ to be =c$ to und]go     

fusion1 exi/s  only 9 t9y quantities4   
,hydrog5-#b1 !re=e1 is ! "o to p9 hopes 
on especially 9  conjunction )          
hydrog5-#c4 ,only #a atom out ( e #fjjj 
hydrog5  atoms is hydrog5-#b1 b t is    
en\gh4 ,!re exi/s a va/ ocean on  e>? t 
is made up almo/ entirely ( wat]        
molecules & 9 ea*  wat] molecule #b     
hydrog5 atoms are pres5t4 ,ev5 if only  
#a 9 #fjjj (  ^! hydrog5 atoms is       
deut]ium t /ill means !re are ab\t      
#ce1jjj billion tons ( deut]ium 9 !     
ocean4    ,:at's m1 x isn't necess>y to 
dig = t deut]ium or to drill  = x4 ,if  
ocean wat] is all[$ to run ?r\gh        
sep>ation plants1 !  deut]ium c be      
extract$ )\t v mu* tr\ble4 ,9 fact1 = ! 
en]gy y c\ld get out ( x1 deut]ium f !  
oceans1 extract$ by  pres5t me?ods & )\t
 all[+ = future improvem5t1 w\ld be     
only "o-hundr$? z exp5sive z coal4    ,!
 deut]ium 9 ! _w's ocean1 if all[$ to   
und]go fusion little  by little1 w\ld   
supply mank9d ) en\gh en]gy to keep u   
go+ at  ! pres5t rate = #ejj1jjj1jjj1jjj

 ye>s4 ,to be sure1 to make  deut]ium   
fusion practical1 x may be necess>y to  
make use ( r>]  sub/ances su* z ! light 
metal li?ium4 ,?is w place a %>p]  limit
 on ! en]gy supply b ev5 if we are      
c>eful1 fusion w\ld  probably supply    
mank9d ) en]gy = z long z mank9d w exi/4
    ,!n1 too1 !re w\ld seem to be no    
dang] ( hydrog5 fusion plants  runn+ out
 ( control4 ,only small quantities (    
deut]ium w\ld be 9  ! process ( fusion  
at any "o "t4 ,if any?+ at all w5t      
wrong1  ! deut]ium supply c\ld be       
automatically cut (f & ! fusion         
process1 ) s little involv$1 w\ld !n /op
 in/antly4 ,moreov]1  !re w\ld be less  
reason to worry ab\t atomic wa/es1 = !  
mo/  dang]\s products--hydrog5-#c &     
neutrons--c\ld be easily tak5 c>e  (4   
,x seems ideal1 b !re is a cat*4 ,h[ev] 
cle> ! !ory1 be=e a  fusion p[] /ation c
 be e/abli%$ "s practical me?od mu/ be  
f\nd to />t ! fusion process1 :i* means 
f9d+ "s way =  atta9+ temp]atures 9 !   
millions ( degrees4    ,"o me?od =      

obta9+ ! necess>y temp]ature 0 kn[n by  
#aide4 ,an  explod+ fission bomb w\ld d 
x4 ,if1 someh[1 ! necess>y  hydrog5-#b 0
 comb9$ ) a fission bomb1 ! explosion   
w\ld set (f  a fusion reaction t w\ld   
greatly multiply ! en]gy releas$4 ,y    
w\ld h 9 effect a 8!rmonucle> bomb04    
7,to ! g5]al public1  ?is 0 commonly    
kn[n z a 8hydrog5 bomb0 or an           
8,h-bomb047    ,9 #aieb ! fir/ fusion   
device 0 explod$ by ! ,unit$ ,/ates 9 ! 
,m>%all ,isl&s4 ,)9 mon?s1 ! ,soviet    
,union _h explod$ "o (  its own & 9 "t  
!rmonucle> bombs ?\s&s ( times z p[]ful 
z ! fir/ fission bomb ov] ,hiro%ima 7   
built & explod$4    ,all !rmonucle>     
bombs h be5 explod$ only = te/ purposes4
 ,ev5  te/+ seems to be dang]\s1 h[ev]1 
at lea/ if x is c>ri$ on 9  ! op5       
atmosph]e4 ,! radioactivity lib]at$     
spreads ov] ! _w  & may d sl[ b         
cumulative damage4      ,controll$      
,fusion    ,h[ev] effective a fusion    
bomb may be 9 lib]at+ va/ quantities (  
en]gy1 x is n :at "o has 9 m9d :5 speak+

 ( a fusion p[]  /ation4 ,! en]gy ( a   
fusion bomb is releas$ all at once & its
  only function is t ( utt] de/ruction4 
,:at is want$ is !  production ( fusion 
en]gy at a l[ & /eady rate--a rate t is 
"u ! control ( human op]ators4    ,!    
sun1 = in/ance1 is a va/ fusion furnace 
#hff1jjj miles across1  b x is a        
controll$ "o--ev5 ?\gh t control is     
ex]t$ by !  imp]sonal laws ( nature4 ,x 
releases en]gy at a v /eady & v  sl[    
rate4 7,! rate is n sl[ 9 human t]ms1 ( 
c\rse1 b />s  sometimes d release _!    
en]gy 9 a mu* m cataclysmic fa%ion4  ,! 
result is a 8sup]nova0 9 :i* = a %ort "t
 a s+le /> w  increase its radiation to 
z mu* z a trillion times its normal     
level47    ,! sun 7or any />7 go+ at its
 normal rate is controll$ & /eady  9 its
 output because ( ! advantage ( huge    
mass4 ,an enorm\s mass1  compos$ ma9ly (
 hydrog51 compresses itself1 ?r\gh its  
equally  enorm\s gravitational field1   
into huge d5sities & temp]atures at  its
 c5t]1 ?us ignit+ ! fusion              

reaction--:ile ! same  gravitational    
field keeps ! sun toge!r aga9/ its      
t5d5cy to  exp&4    ,!re is1 z f> z     
sci5ti/s "k1 no conceivable way (       
conc5trat+  a high gravitational field 9
 ! abs5ce ( ! requir$ mass1 & !         
creation ( controll$ fusion on e>? mu/  
!re=e be done )\t  ! aid ( gravity4 ,)\t
 a huge gravitational =ce we _c         
simultane\sly br+ ab\t sun-c5t] d5sities
 & sun-c5t]  temp]atures2 "o or ! o!r   
mu/ g4    ,on ! :ole1 x w\ld take mu*   
less en]gy to aim at ! temp]atures  ?an 
at ! d5sities & w\ld be mu* m feasible4 
,= ?is reason1  physici/s h be5         
attempt+1 all ?r\gh ! nucle> age1 to    
heat  ?9 wisps ( hydrog5 to enorm\s     
temp]ature4 ,s9ce ! gas is ?91  ! nuclei
 are f>!r ap>t & collide ) ea* o!r f>   
few] times  p] second4 ,to a*ieve fusion
 ignition1 !re=e1 temp]atures mu/ be    
consid]ably high] ?an ^? at ! c5t] ( !  
sun4 ,9 #aidd ,f]mi  calculat$ t x might
 take a temp]ature ( #ej1jjj1jjj to     
ignite a  hydrog5-#c fusion ) hydrog5-#b

 "u e>?ly conditions1 &  #djj1jjj1jjj to
 ignite hydrog5-#b fusion alone4 ,to    
ignite hydrog5-#a  fusion1 :i* is :at   
goes on 9 ! sun 7at a m]e #ae1jjj1jjj71 
physici/s w\ld h to raise _! sights to  
beyond ! billion-degree  m>k4           
,illu/ration3 ,a sup]nova photograph$ on
 ,m>* #aj1 #aice4    ,illu/ration3 ,!   
same /> on ,may #f4    ,?is w\ld make x 
seem almo/ ess5tial to use hydrog5-#c 9 
"o  fa%ion or ano!r4 ,ev5 if x c't be   
prep>$ 9 quantity to beg9  )1 x might be
 =m$ by neutron bomb>dm5t ( li?ium1 ) ! 
neutrons be+ =m$ by ! fusion reaction4  
,9 ?is way1 y w\ld  />t ) li?ium &      
hydrog5-#b plus a little hydrog5-#c4 ,! 
hydrog5-#c is =m$ z fa/ z x is us$ up4  
,al?\gh 9 ! end  hydrog5 is conv]t$ to  
helium 9 a controll$ fusion reaction z 9
  ! sun1 ! individual /eps 9 ! reaction 
"u human control are  q diff]5t f ^? 9 !
 sun4    ,/ill1 ev5 ! temp]atures       
requir$ = hydrog5-#c repres5t an        
enorm\s problem1 p>ticul>ly s9ce !      
temp]ature mu/ n only be  rea*$1 b mu/  

be held = a p]iod ( "t4 7,y c pass a    
piece (  pap] rapidly ?r\gh a c&le flame
 )\t light+ x4 ,x mu/ be  held 9 ! flame
 = a %ort p]iod to give x a *ance to    
heat &  ignite47    ,! ,engli% physici/ 
,john ,david ,lawson 7#aibc-    7 work$ 
out !  requirem5ts 9 #aieg4 ,! "t dep5d$
 on ! d5sity ( ! gas4 ,!  d5s] ! gas1 ! 
%ort] ! p]iod ov] :i* ! temp]ature _h to
  be ma9ta9$4 ,if ! gas is ab\t "o      
hundr$-?\s& times z d5se  z air1 ! prop]
 temp]ature mu/ be held1 "u ! mo/       
favorable  conditions1 = ab\t "o ?\s&? (
 a second4    ,!re are a numb] ( diff]5t
 ways 9 :i* a quantity ( hydrog5 c  be  
heat$ to v high temp]atures--?r\gh      
electric curr5ts1 ?r\gh  magnetic       
fields1 ?r\gh las] beams & s on4 ,z !   
temp]ature goes  up into ! t5s ( ?\s&s (
 degrees1 ! hydrog5 atoms 7or any       
atoms7 are brok5 up into free electrons 
& b>e nuclei4 ,su* a mixture  ( *>g$    
p>ticles is call$ a 8plasma04 ,ev] s9ce 
physici/s h  begun to try to "w ) v hot 
gases1 ) fusion en]gy 9 m9d1  !y h _h to

 /udy ! prop]ties ( su* 8plasma01 & a   
:ole new  sci5ce ( 8plasma physics0 has 
come into exi/5ce4    ,b if y d heat a  
gas to v high temp]atures1 x w t5d to   
exp& & ?9 out to uselessness4 ,h[ c su* 
a sup]-hot gas be  conf9$ 9 a fix$      
volume )\t an enorm\s gravitational     
field to  hold x toge!r8    ,an obvi\s  
answ] w\ld be to place x 9 a conta9]1 b 
no ord9>y  conta9] ( matt] w s]ve to    
hold ! hot gas4 ,y may ?9k ?is  is      
because ! temp]ature ( ! gas w simply   
melt or vaporize  :atev] matt] encloses 
x4 ,?is is n s4 ,al?\gh ! gas is at a  v
 high temp]ature1 x is s ?9 t x has v   
little total heat4  ,x does n h en\gh   
heat to melt ! solid walls ( a conta9]4 
,:at happ5s in/ead is t ! hot plasma    
cools d[n ! mom5t x  t\*es ! solid walls
 & ! entire attempt to heat x is ru9$4  
,:at's m1 if y try to inve/ ! enorm\s   
en]gies requir$ to keep  ! plasma hot   
despite ! cool+ effect ( ! conta9]      
walls1 !n  ! walls w gradually heat &   
melt4 ,nor mu/ "o wait = ! walls  to    

melt & ! plasma to escape be=e f9d+ !   
attempt at fusion  ru9$4 ,ev5 z ! walls 
heat up !y lib]ate "s ( _! own atoms    
into ! plasma & introduce impurities t w
 prev5t ! fusion  reaction4    ,any     
mat]ial conta9] is !re=e out ( ! "q4    
,=tunately1 !re is a nonmat]ial way (   
conf9+ plasma4 ,s9ce  plasma consi/s ( a
 mixture ( electrically *>g$ p>ticles1 x
 c  exp]i5ce electromagnetic            
int]actions4 ,in/ead ( keep+ ! plasma  9
 a mat]ial conta9]1 y c surr\nd x by a  
magnetic field t is  design$ to keep x 9
 place4 ,su* a magnetic field is n      
affect$ by  any heat1 h[ev] great1 & _c 
be a s\rce ( mat]ial impurity4    ,9    
#aicd1 ! ,am]ican physici/ ,will>d      
,h>rison ,b5nett 7#aijc-    7 _h  work$ 
out a !ory deal+ ) ! behavior ( magnetic
 fields  enclos+ plasma4 ,x came to be  
call$ ! 8p9* effect0 because !  magnetic
 field p9*$ ! gas toge!r & held x 9     
place4    ,! fir/ attempt to make use ( 
! p9* effect = conf9+ plasma1  ) ev5tual
 ignition ( fusion 9 m9d1 0 9 #aiea by !

 ,engli%  physici/ ,alan ,alfr$ ,w>e    
7#aibd-    74 ,o!r physici/s foll[$1 n  
only 9 ,great ,brita91 b 9 ! ,unit$     
,/ates & ! ,soviet ,union z  well4    ,!
 fir/ use ( ! p9* effect 0 to conf9e !  
plasma 9 a  cyl9d]4 ,?is1 h[ev]1 c\ld n 
be made to "w4 ,! situation 0  too      
un/able4 ,! plasma 0 held mom5t>ily1 !n 
wri!d & broke  up4    ,illu/ration3     
,plasma 9 a magnetic field4             
,illu/ration3 ,enorm\s ma*9es & complex 
equipm5t1 su* z !  ,scyllac ma*9e %[n   
above1 are requir$ = nucle> fusion      
rese>*4    ,attempts 7 made to remove ! 
in/ability4 ,! field 0 s design$  z to  
be /rong] at ! ends ( ! cyl9d] ?an      
else:]e4 ,!  p>ticles 9 ! plasma w\ld   
/ream t[>d "o end or ano!r & w\ld  !n   
b\nce back produc+ a s-call$ 8magnetic  
mirror04    ,9 #aiea ! ,am]ican physici/
 ,lyman ,spitz]1 ,jr4 7#aiad-    7 _h   
work$  out ! !oretical b5efits to be    
d]iv$ f a conta9] twi/$ into  a         
figure-eight %ape4 ,ev5tually1 su*      
devices 7 built & call$  8/ell>ators0 f 

! ,lat9 ^w = 8/>01 because x 0 hop$ t  x
 w\ld produce ! conditions t w\ld all[ !
 sort ( fusion  reactions t w5t on 9    
/>s4    ,all ?r\gh ! #aiejs & #aifjs1   
physici/s h be5 sl[ly in*+  t[>d _!     
goal1 rea*+ high] & high] temp]atures & 
hold+  !m = long] & long] p]iods 9 d5s] 
& d5s] gases4    ,9 #aifi ! ,soviet     
,union us$ a device call$ 8,tokamak-#c0 
7a ,russian  abbreviation = _! phrase = 
8electric-magnetic07 to keep a supply  (
 hydrog5-#b1 a million? z d5se z air1 9 
place :ile heat+ x to  t5s ( millions ( 
degrees = a hundr$? ( a second4    ,a   
little d5s]1 a little hott]1 a little   
long]--& controll$ fusion  might become 
possible4#e                             
,,beyond ,,fusion      ,antimatt]    ,is
 !re any?+ t lies beyond fusion8    ,:5 
hydrog5 und]goes fusion & becomes       
helium1 only #j4g ( !  orig9al mass ( ! 
hydrog5 is conv]t$ to en]gy4 ,is x      
possible to  take a quantity ( mass &   
conv]t all ( x1 e bit1 to en]gy8        
,surely t w\ld be ! ultimate en]gy      

s\rce4 ,mass = mass1 t  w\ld deliv] #adj
 times z mu* en]gy z hydrog5 fusion     
w\ld2 x  w\ld be z f> beyond hydrog5    
fusion z hydrog5 fusion is beyond       
uranium fission4    ,&1 z a matt] (     
fact1 total annihilation ( matt] is     
conceivable  "u "s circum/ances4    ,9  
#aibh ! ,engli% physici/ ,paul ,adri5   
,maurice ,dirac 7#aijb-    7  pres5t$ a 
treatm5t ( ! electron's prop]ties t made
 x appe>  z ?\gh !re ought also to exi/ 
a p>ticle exactly l ! electron  9 e     
respect except t x w\ld be opposite 9   
*>ge4 ,x w\ld  c>ry a positive electric 
*>ge exactly z l>ge z ! electron's      
negative "o4    ,if ! electron is a     
p>ticle1 ?is sugge/$ positively *>g$ tw9
  w\ld be an 8antip>ticle04 7,! prefix  
comes f a ,greek ^w mean+  8opposite047 
,illu/ration3 ,p4 ,a4 ,m4 ,dirac        
,illu/ration3 ,! fir/ picture ( !       
positron 7left7 0 tak5 9 a  ,wilson cl\d
 *amb]4 ,on ! "r is ,c4 ,d4 ,&]son1 !   
discov]] (  ! positron4    ,! proton is 
n ! electron's antip>ticle4 ,?\gh a     

proton c>ries  ! necess>y positive *>ge 
t is exactly z l>ge z ! negative  *>ge (
 ! electron1 ! proton has a mu* l>g]    
mass ?an !  electron has4 ,dirac's !ory 
requir$ t ! antip>ticle h !  same mass z
 ! p>ticle to :i* x correspond$4    ,9  
#aicb ,c4 ,d4 ,&]son 0 /udy+ ! impact ( 
cosmic p>ticles on  lead4 ,9 ! process1 
he discov]$ signs ( a p>ticle t left    
tracks  exactly l ^? ( an electron1 b   
tracks t curv$ ! wrong way  9 a magnetic
 field4 ,?is 0 a sure sign t x _h an    
electric *>ge  opposite to t ( !        
electron4 ,he _h1 9 %ort1 discov]$ !    
electron's antip>ticle & ?is came to be 
call$ ! 8positron04    ,positrons 7 soon
 detect$ else:]e too4 ,"s radioactive   
isotopes1  =m$ 9 ! laboratory by !      
,joliot-,curies & by o!rs1 7 f\nd  to   
emit positive beta p>ticles--positrons r
 ?an electrons4 ,:5 an  ord9>y beta     
p>ticle1 or electron1 0 emitt$ f a      
nucleus1 a  neutron )9 ! nucleus 0      
conv]t$ to a proton4 ,:5 a positive     
beta p>ticle1 a positron1 0 emitt$1 !   

rev]se happ5$--a proton  0 conv]t$ to a 
neutron4    ,a positron1 h[ev]1 does n  
endure long aft] =mation4 ,all ab\t x  7
 atoms conta9+ electrons4 ,x c\ld n move
 = m ?an a  million? ( a second or s    
be=e x enc\nt]$ "o ( ^?  electrons4 ,:5 
x did1 !re 0 an attraction betwe5 ! two1
 s9ce  !y 7 ( opposite electric *>ge4   
,briefly !y might circle ea*  o!r 7to =m
 a comb9ation call$ 8positronium07 b    
only v  briefly4 ,!n !y collid$ &1 s9ce 
!y 7 opposites1 ea*  cancell$ ! o!r4    
,! process :]eby an electron & a        
positron met & cancell$ is  call$       
8mutual annihilation04 ,n ev]y?+ 0 gone1
 ?\gh4 ,! mass1  9 disappe>+1 0 conv]t$ 
into ! equival5t am\nt ( en]gy1  :i*    
made its appe>ance 9 ! =m ( "o or m     
gamma rays4    7,x works ! o!r way1 too4
 ,a gamma ray ( suffici5t en]gy c be    
trans=m$ into an electron & a positron4 
,?is ph5om5on1 call$  8pair production01
 0 obs]v$ z e>ly z #aicj b 0 only       
prop]ly  und]/ood aft] ! discov]y ( !   
positron47    ,( c\rse1 ! mass (        

electrons & positrons is v small & !    
am\nt ( en]gy releas$ p] electron is n  
enorm\sly high4 ,/ill1  ,dirac's orig9al
 !ory ( antip>ticles 0 n conf9$ to      
electrons4  ,by 8 !ory1 any p>ticle     
ought to h "s correspond+  antip>ticle4 
,correspond+ to ! proton1 = in/ance1 !re
 ought to  be an 8antiproton04 ,?is w\ld
 be j z massive z ! proton &  w\ld c>ry 
a negative *>ge j z l>ge z ! proton's   
positive  *>ge4    ,an antiproton1      
h[ev]1 is #ahcf times z massive z a     
positron4 ,x w\ld  take gamma rays or   
cosmic p>ticles ) #ahcf times z mu*     
en]gy to  =m ! proton-antiproton pair z 
w\ld suffice = !  electron-positron     
pair4 ,cosmic p>ticles ( ! necess>y     
en]gies  exi/$ b !y 7 r>e & ! *ance (   
someone be+ pres5t )  a p>ticle detector
 j z a r>e sup]-en]getic cosmic p>ticle 
happ5$ to =m a proton-antiproton pair 0 
v small4    ,illu/ration3 ,! ,bevatron  
began op]ation 9 #aied4    ,physici/s _h
 to wait until !y _h succe$$ 9 design+  
p>ticle  accel]ators t w\ld produce     

en\gh en]gy to all[ ! creation (        
proton-antiproton pairs4 ,?is came ab\t 
9 ! e>ly #aiejs :5 a  device call$ !    
8,cosmotron0 0 built at ,brookhav5      
,national  ,laboratory 9 ,long ,isl& 9  
#aieb & ano!r call$ ! 8,bevatron0 at  ! 
,univ]sity ( ,cali=nia 9 ,b]keley 9     
#aied4    ,us+ ! ,bevatron 9 #aief1     
,segr 7! discov]] ( te*netium :o _h1  by
 t "t1 emigrat$ to ! ,unit$ ,/ates71 !  
,am]ican physici/  ,ow5 ,*amb]la9       
7#aibj-    71 & o!rs succe$$ 9 detect+ !
  antiproton4    ,! antiproton 0 z      
unlikely to la/ z long z ! positron 04  
,x  0 surr\nd$ by myriads (             
proton-conta9+ nuclei & 9 a t9y         
fraction ( a second x w\ld enc\nt] "o4  
,! antiproton & !  proton also und]w5t  
mutual annihilation1 b hav+ #ahcf times 
!  mass1 !y produc$ #ahcf times ! en]gy 
t 0 produc$ 9 ! case  ( an electron & a 
positron4    ,!re 0 ev5 an 8ant9eutron01
 a p>ticle report$ 9 #aief by !         
,italian-,am]ican physici/ ,ore/e       
,piccioni 7#aiae-    7 & 8  co-work]s4  

,s9ce ! neutron has no *>ge1 !          
ant9eutron has no  *>ge ei!r1 & "o might
 wond] h[ ! ant9eutron w\ld diff]  f !  
neutron !n4 ,actually1 bo? h a small    
magnetic field4 ,9  ! neutron ! magnetic
 field is po9t$ 9 "o direction )        
ref]5ce to ! neutron's sp92 9 !         
ant9eutron x is po9t$ 9 !  o!r4         
,illu/ration3 ,bubble *amb] photograph (
 an antiproton  annihilation4    ,9     
#aife ! ,am]ican physici/ ,leon ,max    
,l$]man 7#aibb-    7 & 8  co-work]s     
produc$ a comb9ation ( an antiproton &  
an ant9eutron  t toge!r =m$ an          
8antideut]on01 :i* is ! nucleus (       
antihydrog5-#b4    ,?is is good en\gh to
 demon/rate t if antip>ticles exi/$ by  
!mselves )\t ! int]f]+ pres5ce ( ord9>y 
p>ticles1 !y  c\ld =m 8antimatt]01 :i*  
w\ld be precisely id5tical )  ord9>y    
matt] 9 e way except = ! fact t electric
 *>ges  & magnetic fields w\ld be turn$ 
ar\nd4    ,if antimatt] 7 available to  
u1 & if we c\ld control ! mann]  9 :i* x
 unit$ ) matt]1 we w\ld h a s\rce (     

en]gy mu*  great] &1 p]haps1 simpl] to  
produce ?an w\ld be involv$ 9  hydrog5  
fusion4    ,to be sure1 !re is no       
antimatt] on e>?1 except = !            
submicroscopic am\nts t are =m$ by !    
input ( trem5d\s  en]gies4 ,nor does    
anyone "k ( any conceivable way ( =m+   
antimatt] at less en]gy ?an t produc$ by
 mutual annihilation1 s  t we might say 
t mank9d c nev] make an en]gy pr(it out 
(  x--except t ) ! memory ( ,ru!r=d's   
pr$iction t nucle>  en]gy ( any k9d c\ld
 nev] be tapp$1 "o hesitates to be      
pessimi/ic ab\t any?+4      ,! ,unkn[n  
,physical !ory makes x seem t p>ticles &
 antip>ticles ought to  exi/ 9 ! univ]se
 9 equal quantities4 ,yet on e>? 7&1 we 
c be  q c]ta91 9 ! re/ ( ! sol> sy/em & 
ev51 v likely1 9  ! re/ ( ! galaxy7     
protons1 neutrons1 & electrons are      
common1  :ile antiprotons1 ant9eutrons1 
& positrons are exce$+ly r>e4    ,c\ld x
 be t :5 ! univ]se 0 fir/ =m$ !re 7     
inde$  equal quantities ( p>ticles &    
antip>ticles b t !y 7  someh[ segregat$1

 p]haps into galaxies & 8antigalaxies08 
,if s1  !re might occasionally be       
collisions ( a galaxy & an antigalaxy  )
 ! evolution ( va/ quantities ( en]gy z 
mutual annihilation  on a cosmic scale  
takes place4    ,!re are1 9 fact1 places
 9 ! heav5s :]e radiation is unusually  
high 9 quantity & 9 en]gy4 ,c we be     
witness+ su* enorm\s  mutual            
annihilation8    ,inde$1 x is n altoge!r
 inconceivable t we may /ill h new      
types ( =ces & new s\rces ( en]gy to    
discov]4 ,until ab\t #aijj1  no "o      
suspect$ ! exi/5ce ( nucle> en]gy4 ,are 
we q sure n[  t nucle> en]gy br+s u to !
 end1 & t !re is n a =m  ( en]gy m      
subtle /ill1 & great]8    ,9 #aifb1 =   
in/ance1 c]ta9 puzzl+ objects call$     
8quas>s0 7  discov]$ f> out 9 space1 a  
billion light-ye>s or m away f u4  ,ea* 
"o %9es f #aj to #ajj times z           
brilliantly z an entire  ord9>y galaxy  
does1 & yet may be no m ?an a           
hundr$-?\s&?  z wide z a galaxy4    ,?is
 is some?+ l f9d+ an object #aj miles   

across t deliv]s  z mu* total light z   
#ajj suns4    ,x is v h>d to und]/& :]e 
all t en]gy comes f & :y  x %\ld be     
conc5trat$ into s t9y a volume4         
,a/ronom]s h tri$  to expla9 x 9 t]ms ( 
! f\r int]actions n[ kn[n1 b is x       
possible t !re is a fif? great] ?an any 
( ! f\r8    ,if s1 x is n impossible t  
ev5tually man's re/less bra9 may  come  
to und]/& & ev5 utilize x4              
,,footnotes      #a,see ,! ,fir/        
,reactor1 ano!r booklet 9 ?is s]ies4    
#b,see ,nucle> ,reactors & ,nucle> ,p[] 
,plants1 companion booklets      9 ?is  
s]ies4    #c,see ,bre$] ,reactors1 ano!r
 booklet 9 ?is s]ies4    #d,see         
,?orium--& ! ,?ird ,fuel1 ano!r booklet 
9 ?is s]ies4    #e,see ,controll$       
,nucle> ,fusion1 ano!r booklet 9 ?is    
s]ies4                                  
,,quotation ,,cr$it        ,inside front
 cov]    ,copyright  by ,abel>d-,%uman1 
,ltd41 ,new ,york4                      
,repr9t$ by p]mission f ,inside ! ,atom1
                          ,isaac        

,asimov1 #aiff4                         
,,read+ ,,li/      ,basic ,books        
,basic ,laws ( ,matt] 7revis$ edition71 
,h>rie ,s4 ,w4 ,massey &    ,ar?ur ,r4  
,qu9ton1 ,h]ald ,books1 ,bronxville1    
,new ,york1 #aife1 #agh pp41    #c4ge4  
,grades #g-i4 ,a nonte*nical pres5tation
 ( atoms & ! laws    gov]n+ _! behavior4
      ,biography ( ,physics1 ,george    
,gam[1 ,h>p]  ,r[1 ,publi%]s1 ,new      
,york1 #aifa1 #cch pp41 #f4ej 7h>dback72
 #b4ge 7pap]back74 ,grades #i-ab4    ,a 
hi/ory ( !oretical physics4             
,discov]] ( ,x ,rays3 ,wilhelm ,conrad  
,ro5tg51 ,arnulf ,k4 ,e/]]1    ,julian  
,messn]1 ,new ,york1 #aifh1 #aia pp41   
#c4ej4 ,grades #g-aj4 ,?is    int]e/+   
biography includes a brief1 b v helpful1
 pron\nc+    gazette] ( ! ,g]man1       
,swiss1 & ,dut* names 9 ! text4         
,erne/ ,ru!r=d3 ,ar*itect ( ! ,atom1    
,pet] ,kelman & ,a4 ,h>ris    ,/one1    
,pr5tice-,hall1 ,inc41 ,englewood       
,cliffs1 ,new ,j]sey1 #aifi1 #gb    pp41
 #c4ie4 ,grades #e-g4 ,a well-done      

biography ( ?is fam\s atomic    sci5ti/4
 ,_m ( ! draw+s illu/rate !oretical     
ideas v well    = ! elem5t>y grades4 ,a 
gloss>y is includ$4      ,enrico ,f]mi3 
,atomic ,pione]1 ,doris ,fab]1          
,pr5tice-,hall1 ,inc41    ,englewood    
,cliffs1 ,new ,j]sey1 #aiff1 #hf pp41   
#c4ie4 ,grades #e-h4 ,a    biography ( !
 man :o built ! fir/ reactor4           
,giant ( ! ,atom3 ,erne/ ,ru!r=d1 ,rob9 
,mc,kown1 ,julian ,messn]1    ,new      
,york1 #aifb1 #aia pp41 #c4ej4 ,grades  
#g-ab4 ,! life &    accompli%m5ts ( a   
great physici/4      ,! ,hi/ory ( !     
,atomic ,bomb1 ,mi*ael ,bl[1 ,am]ican   
,h]itage    ,publi%+ ,company1 ,inc41   
,new ,york1 #aifh1 #aej pp41 #e4ie4     
,grades #e-i4    ,?is sumptu\sly        
illu/rat$ hi/ory provides an in=mative  
explanation ( nucle> physics 9 addition 
to compreh5sive cov]age    ( ! bomb's   
developm5t & use4      ,inside ! ,atom1 
,isaac ,asimov1 ,abel>d-,s*uman1 ,ltd41 
,new ,york1    #aiff1 #aig pp41 #d4jj4  
,grades #g-aj4 ,?is compreh5sive1       

well-writt5    text expla9s nucle> en]gy
 & its applications4      ,madame       
,curie3 ,a ,biography1 ,eve ,curie1     
translat$ by ,v9c5t ,%eean1    ,d\bl$ay 
& ,company1 ,inc41 ,new ,york1 #aicg1   
#che pp41 #e4ie    7h>dback72 #j4ie     
7pap]back74 ,grades #i-ab4 ,?is sup]b   
biography1    :i* won ! #aicg ,national 
,book ,aw>d = ,nonfiction1 illu/rates   
dramatically ! full spectrum ( ,m>ie    
,curie's life4      ,m5 ,:o ,ma/]$ !    
,atom1 ,rob]t ,silv]b]g1 ,g4 ,p4        
,putnam's ,sons1    ,new ,york1 #aife1  
#aic pp41 #c4di4 ,grades #g-i4 ,atomic  
en]gy hi/ory is    told ?r\gh ! "w (    
pione] sci5ti/s f ,?ales to pres5t-day  
rese>*]s4      ,! ,neutron ,/ory1       
,donald ,j4 ,hughes1 ,d\bl$ay &         
,company1 ,inc41    ,new ,york1 #aiei1  
#aeh pp41 out ( pr9t4 ,grades #g-i4 ,a  
sub/antial &    int]e/+ acc\nt ( neutron
 physics4      ,niels ,bohr3 ,! ,man ,:o
 ,mapp$ ! ,atom1 ,rob]t ,silv]b]g1      
,mac,rae    ,smi? ,company1             
,philadelphia1 ,p5nsylvania1 #aife1 #ahi

 pp41 #c4ie4    ,grades #h-ab4 ,an      
excit+1 susp5seful1 & humor\s biography 
( "o    ( ! pione]s 9 atomic en]gy4     
,includes a gloss>y & ref]5ces4      ,! 
,que/ion]s3 ,physici/s & ! ,quantum     
,!ory1 ,b>b>a ,lovett    ,cl9e1 ,cr[ell 
,colli] & ,mac,millan1 ,inc41 ,new      
,york1 #aife1 #bgd pp41    #e4jj        
7h>dback72 available 9 pap]back ) !     
title ,m5 ,:o ,made    ,a ,new ,physics3
 ,physici/s & ! ,quantum ,!ory1 ,new    
,am]ican    ,libr>y1 ,inc41 ,new ,york1 
#j4ge4 ,grades #i-ab4 ,an exceptionally 
well-del9eat$ & p]sonable acc\nt ( !    
developm5t ( !    quantum !ory by       
physici/s 9 ! fir/ qu>t] ( ?is c5tury4  
,! ,re/less ,atom1 ,alfr$ ,rom]1        
,d\bl$ay & ,company1 ,inc41 ,new        
,york1 #aifj1 #aih pp41 #a4be4 ,grades  
#i-ab4 ,a /imulat+ nonma!matical        
acc\nt ( ! classic e>ly exp]im5ts t     
advanc$ k ab\t    atomic p>ticles4      
,roads to ,discov]y1 ,ralph ,e4 ,lapp1  
,h>p] & ,r[1 ,publi%]s1 ,new    ,york1  
#aifj1 #aia pp41 out ( pr9t4 ,grades    

#aj-ab4 ,hi/orical survey (    nucle>   
physics beg9n+ ) ,ro5tg5's discov]y ( ,x
 rays &    conclud+ ) ! discov]ies ( !  
r>e elem5ts4      ,secret ( ! ,my/]i\s  
,rays3 ,! ,discov]y ( ,nucle> ,en]gy1   
,vivian ,grey1 ,basic ,books1 ,inc41    
,publi%]s1 ,new ,york1 #aiff1 #abj pp41 
#c4ie4 ,grades #d-h4 ,?is out/&+ hi/ory 
( nucle> rese>* f    ,ro5tg5 to ,f]mi is
 dramatically pres5t$4 ,! unc]ta9ty ( ! 
unkn[n1 ! accid5tal discov]y & ! (t5    
l5g?y & t$i\s    rese>* are wov5 9 ?is  
/ory ( sci5ti/s f ar\nd ! _w    :o pool$
 _! k & exp]i5ce to unlock 8! secrets ( 
! my/]i\s rays04      ,wilhelm ,ro5tg5 &
 ! ,discov]y ( ,x ,rays1 ,b]n ,dibn]1   
,frankl9    ,watts1 ,inc41 ,new ,york1  
#aifh1 #adi pp41 #b4ie4 ,grades #e-h4   
,?is detail$    biography1 illu/rat$ )  
l9e draw+s1 hi/orical photographs1 &    
pap]s1 is a f9e addition to ,watts'     
8,immortals ( ,sci5ce0 ,s]ies4          
,work+ ) ,atoms1 ,otto ,r4 ,fris*1      
,basic ,books1 ,inc41 ,new ,york1       
#aife1 #if pp41 #d4ie4 ,grades #i-ab4   

,dr4 ,fris* pres5ts a hi/ory (    nucle>
 en]gy rese>* & provides exp]im5ts = !  
read]4 ,he    gives a p]sonal acc\nt ( !
 pione]+ "w 9 :i* he & ,lise    ,meitn] 
expla9$ ! splitt+ ( uranium & introduc$ 
! t]m    8nucle> fission04      ,advanc$
 ,books      ,an ,am]ican ,g5ius3 ,!    
,life ( ,erne/ ,orl&o ,lawr5ce1 ,h]b]t  
,*ilds1 ,e4 ,p4 ,dutton & ,company1     
,inc41 ,new ,york1 #aifh1 #egf pp41     
#ab4ie4 ,?is well-writt51 sci5tifically 
accurate1 & v    int]e/+ biography      
captures ! excitem5t ( ,lawr5ce's life4 
,erne/ ,lawr5ce 0 ! inv5tor ( !         
cyclotron1 a major memb] (    ! w>time  
atomic en]gy developm5t1 & ! director ( 
!    ,lawr5ce ,radiation ,laboratory4   
,! ,atom & ,its ,nucleus1 ,george ,gam[1
 ,pr5tice-,hall1 ,inc41    ,englewood   
,cliffs1 ,new ,j]sey1 #aifa1 #aec pp41  
#a4be4 ,a popul>-level    discussion (  
nucle> /ructure & ! applications (      
nucle>    en]gy4      ,atomic ,en]gy =  
,milit>y ,purposes1 ,h5ry ,d4 ,smy?1    
,pr9ceton    ,univ]sity ,press1         

,pr9ceton1 ,new ,j]sey1 #aide1 #cjh pp41
 #d4jj4 ,a    complete acc\nt ( ! w>time
 project t develop$ ! fir/    nucle>    
weapons & ( ! consid]ations t prompt$ _!
 use4      ,atomic ,que/1 ,ar?ur ,h4    
,compton1 ,ox=d ,univ]sity ,press1      
,inc41 ,new    ,york1 #aief1 #cgj pp41  
#g4ie4 ,a p]sonal n>rative ( ! rese>* t 
l$ to ! release ( atomic en]gy on a     
useful scale by a sci5ti/    :o play$ a 
pr9cipal "p 9 ! atomic bomb project dur+
 ,_w    ,w> ,,ii4      ,! ,atomi/s      
7#ahje-aicc71 ,basil ,s*onl&1 ,ox=d     
,univ]sity    ,press1 ,inc41 ,new ,york1
 #aifh1 #aih pp41 #e4fj4 ,?is book1 :i* 
c be    und]/ood by anyone :o has _h a  
high s*ool physics c\rse1    pres5ts    
atomic !ory developm5t f ,dalton ?r\gh  
,bohr4 ,x    a*ieves a good balance     
betwe5 popul> treatm5ts & highly        
te*nical works )\t slight+ ! te*nical   
aspects4      ,atoms 9 ! ,family3 ,my   
,life ) ,enrico ,f]mi1 ,laura ,f]mi1    
,*icago    ,univ]sity ,press1 ,*icago1  
,ill9ois1 #aied1 #bfg pp41 #e4jj        

7h>dback72    #b4de 7pap]back74 ,laura  
,f]mi writes ab\t h] husb&1 ,enrico     
,f]mi1    ! physici/ :o l$ ! gr\p t     
built ! fir/ nucle> reactor4      ,!    
,born-,e9/e9 ,lett]s3 ,! ,correspond5ce 
,betwe5 ,alb]t ,e9/e9    & ,max & ,h$wig
 ,born f #aiaf to #aiee1 comm5t>ies by  
,max ,born1    translat$ by ,ir5e ,born1
 ,walk] & ,company1 #aiga1 #bdj pp41    
#h4ej4    ,^! int]e/+ lett]s reveal !   
sci5tific & p]sonal lives (    ^! two   
atomic sci5ti/s4      ,e9/e93 ,8 ,life &
 ,times1 ,philipp ,frank1 ,alfr$ ,a4    
,knopf1 ,inc41    ,new ,york1 #aiec1    
#bih pp41 #f4ie4 ,a brilliant biography 
t reveals !    ri*ness ( ,e9/e9's life &
 "w & ! trem5d\s impact he made    ^u   
physics4      ,enrico ,f]mi1 ,physici/1 
,emilio ,segr1 ,*icago ,univ]sity       
,press1    ,*icago1 ,ill9ois1 #aigj1    
#bhh pp41 #f4ie4 ,?is biography tells ( 
,enrico ,f]mi's intellectual hi/ory1    
a*ievem5ts1 & 8 sci5tific    /yle4 ,!   
sci5tific problems fac$ or solv$ by     
,f]mi are expla9$    9 layman's t]ms4   

,emilio ,segr 0 a fri5d & sci5tific     
collaborator :o work$ ) ,f]mi = _m ye>s4
      ,an ,introduction to ,physical    
,sci5ce3 ,! ,_w ( ,atoms 7second        
edition71 ,john ,j4 ,g4 ,mc,cue1 ,!     
,ronald ,press ,company1 ,new ,york1    
#aifc1    #gge pp41 #i4ej4 ,?is textbook
 0 writt5 = college humanities          
/ud5ts4      ,j4 ,j4 ,?omson3 ,discov]] 
( ! ,electron1 ,george ,?omson1 ,d\bl$ay
    & ,company1 ,inc41 ,new ,york1      
#aiff1 #bdj pp41 #a4de4 ,?is biography1 
writt5 by ,j4 ,j4 ,?omson's son1        
describes 8 rese>* at ! fam$    ,cav5di%
 ,laboratory 9 ,cambridge1 ,engl&4      
,john ,dalton & ! ,atom1 ,frank         
,gre5away1 ,cornell ,univ]sity ,press1  
,i?aca1 ,new ,york1 #aiff1 #bef pp41    
#g4ej4 ,a biography = ! g5]al    read] &
 ! high s*ool sci5ce /ud5t4 ,dalton is  
fam\s = 8    developm5t ( *emical       
comb9ations bas$ on atomic !ory4 ,?is   
provid$ ! basis = mod]n /ructural !ories
 ( *emi/ry4      ,john ,dalton & !      
,atomic ,!ory3 ,! ,biography ( a        

,natural    ,philosoph]1 ,elizabe? ,c4  
,patt]son1 ,d\bl$ay & ,company1 ,inc41  
,new    ,york1 #aigj1 #cbj pp41 #f4ie   
7h>dback72 #a4ie 7pap]back74 ,! drama ( 
,dalton's life--8 rigor\s self-tea*+1   
sci5tific "w1 &    /ruggle to ov]come   
class b>ri]s 9 #ai? c5tury ,engl&--is   
well    pres5t$4 ,quotations f lett]s1  
di>ies1 & publi%$ works give    a cle>  
picture ( ,dalton's atomic !ory rese>* &
 8 "t4      ,man-made ,transuranium     
,elem5ts1 ,gl5n ,t4 ,seaborg1 ,pr5tice  
,hall1    ,inc41 ,englewood ,cliffs1    
,new ,j]sey1 #aifc1 #abj pp41 #f4ie     
7h>dback72    #b4ie 7pap]back74 ,!      
discov]y1 prop]ties1 & applications (   
elem5ts heavi] ?an uranium are consid]$ 
9 ?is book1 :i* is    design$ z an      
introduction to ! subject4 ,gl5n        
,seaborg 0    co-discov]] ( n9e ( !     
twelve transuranium elem5ts4      ,!    
,nature ( ,matt]3 ,physical ,!ory f     
,?ales to ,f]mi1 ,g9e/ra    ,amaldi1    
translat$ by ,pet] ,a/bury1 ,*icago     
,univ]sity ,press1    ,*icago1 ,ill9ois1

 #aiff1 #ccb pp41 #e4ie4 ,a nonte*nical 
hi/ory (    atomic en]gy4      ,niels   
,bohr3 ,8 ,life & ,"w z ,se5 by ,8      
,fri5ds & ,colleagues1    ,s4 ,roz5tal  
7,editor71 ,john ,wiley & ,sons1 ,inc41 
,new ,york1 #aifg1 #cee    pp41 #e4ie4  
,an articulate & s*ol>ly biography by ! 
fri5ds &    co-work]s ( ?is out/&+      
atomic pione]4      ,niels ,bohr3 ,!    
,man1 ,8 ,sci5ce1 & ! ,_w ,!y ,*ang$1   
,ru?    ,moore1 ,alfr$ ,a4 ,knopf1      
,inc41 ,new ,york1 #aiff1 #dcf pp41     
#g4ie4 ,an    int]e/+ biography ( "o ( !
 pione]s 9 ! /udy ( !    int]nal        
/ructure ( ! atom4      ,otto ,hahn3 ,my
 ,life1 ,otto ,hahn1 translat$ by ,erne/
 ,kais] &    ,ei?ne ,wilk9s1 ,h]d] &    
,h]d]1 ,inc41 ,new ,york1 #aigj1 #bdj   
pp41    #f4ej4 ,autobiography ( ! man :o
 discov]$ t ! atom c\ld be    split4    
,otto ,hahn3 ,a ,sci5tific              
,autobiography1 ,otto ,hahn1 ,willy     
,ley1 editor    & translator1 ,*>les    
,scribn]'s ,sons1 ,new ,york1 #aiff1    
#cbj pp41    #i4ie4 ,otto ,hahn1 w9n] ( 

! #aidd ,nobel ,prize = 8 "w 9    atomic
 fission1 reviews ! pione] days 9 :i* a 
new sci5ce 0    creat$1 & ! role he     
play$ 9 its developm5t4      ,physics & 
,beyond3 ,enc\nt]s & ,conv]sations1     
,w]n] ,heis5b]g1    translat$ by ,ar?ur 
,j4 ,pom]ans1 ,h>p] & ,r[1 ,publi%]s1   
,new    ,york1 #aigj1 #bdg pp41 #g4ie4  
,w]n] ,heis5b]g1 a ,nobel ,prize        
physici/1 pres5ts 8 autobiography 9 ! =m
 ( conv]sations    ) su* m5 z ,max      
,planck1 ,alb]t ,e9/e91 ,niels ,bohr1   
,erne/    ,ru!r=d1 ,otto ,hahn1 &       
,enrico ,f]mi4      ,physics = ,poets1  
,rob]t ,h4 ,m>*1 ,mc,graw-,hill ,book   
,company1 ,new4    ,york1 #aigj1 #cjb   
pp41 #g4ej4 ,a physics textbook =       
nonsci5ce    /ud5ts4 ,! book cov]s c]ta9
 developm5ts ( classical me*anics1      
relativity1 & atomic & quantum physics4 
,) ?is book ! au?or    won ! #aiga      
,am]ican ,in/itute ( ,physics--,u4 ,s4  
,/eel ,f\ndation    ,sci5ce ,writ+ ,aw>d
 9 ,physics & ,a/ronomy4      ,s\rcebook
 on ,atomic ,en]gy 7?ird edition71      

,samuel ,glas/one1 ,van    ,no/r&       
,re9hold ,company1 ,new ,york1 #aifg1   
#hhc pp41 #ae4jj4 ,an    excell5t /&>d  
ref]5ce "w1 writt5 = bo? sci5ti/s & !   
g5]al public4      ,! ,swift ,ye>s3 ,!  
,rob]t ,opp5heim] ,/ory1 ,pet]          
,mi*elmore1    ,dodd1 ,mead & ,company1 
,new ,york1 #aifi1 #bgc pp41 #f4ie4     
,opp5heim]'s    complex p]sonality is   
del9eat$ 9 ?is well-writt5 biography4 ,9
    ! bibliography is a li/ ( books t   
,opp5heim] felt 8_h done    ! mo/ to    
%ape 8 vocational attitude & philosophy 
( life04      ,! ,_w ( ! ,atom1 #b      
volumes1 ,h5ry ,a4 ,boorse & ,lloyd     
,motz    7,eds471 ,basic ,books1 ,inc41 
,publi%]s1 ,new ,york1 #aiff1 #ahgc pp41
    #ce4jj4 ,conta9s ! actual text (    
l&m>k docum5ts 9 ! hi/ory    ( atomic   
physics1 ea* prec$$ by comm5t>y t places
 x 9 !    context ( ! discov]]'s p]sonal
 life & 9 ! conditions    prevail+ 9    
sci5ce & 9 society 9 8 "t4              
,photo ,cr$its        ,page fac+ inside 
,! 8,horsehead0 ,nebula 9 ,orion4 ,hale 

cov]                 ,obs]vatories4     
,au?or's ,photo        ,jay ,k4 ,kle9   
,cont5ts page         ,lick ,obs]vatory 
#aaf                   ,samuel ,a4      
,g\dsmit    #aah                   ,f   
,atoms 9 ! ,family3 ,my ,life ,) ,enrico
                          ,f]mi1 ,laura 
,f]mi1 #aied4 ,copyright  by !          
,univ]sity ( ,*icago ,press4    #abj    
,top r[1 left1 ,in/itut fur             
,radium-=s*ung und                      
,kemphysik1 "r1 ,lotte ,meitn]-,graff1  
middle                          r[1     
left1 ,nobel ,in/itute1 "r1 ,erne/      
,orl&o                          ,lawr5ce
 ,b]keley ,laboratory2 bottom r[1 "r1   
,erne/ ,orl&o ,lawr5ce ,b]keley         
,laboratory1                            
left1 ,p4 ,h4 ,abelson4    #abc         
,addison-,wesley ,publi%+ ,company      
#acj                   ,top1 ,ike ,v]ne2
 bottom1 ,oak ,ridge ,national          
,laboratory4    #acb  #acc              
,lett] & ,roosevelt picture f ! ,frankl9
 ,d4                          ,roosevelt

 ,libr>y2 ,johan ,hagemey]4    #acf     
#acg             ,argonne ,national     
,laboratory    #ada                     
,u4 ,s4 ,navy    #adc                   
,"r1 ,we/+h\se ,electric ,corporation   
#ade                   ,argonne         
,national ,laboratory    #aeb           
,lick ,obs]vatory    #aee               
,gulf ,en]gy & ,environm5tal ,sy/ems    
#aef                   ,los ,alamos     
,sci5tific ,laboratory    #aeh          
,nobel ,in/itute    #aei                
,left1 ,c4 ,d4 ,&]son2 "r1 ,nobel       
,in/itute4    #afa                      
,erne/ ,orl&o ,lawr5ce ,b]keley         
,laboratory                         ,u4 
,s4 ,,gov]nm5t ,,pr9t+ ,,(fice3 #aigb - 
#gdg-ahi_/b      ,! ,u4 ,s4 ,atomic     
,en]gy ,commission publi%es ?is s]ies ( 
in=mation  booklets = ! g5]al public4   
,^! booklets expla9 ! _m uses (  nucle> 
en]gy4    ,! booklets are li/$ bel[ by  
subject category4      ,g5]al ,int]e/   
,,0-#jji ,atomic ,en]gy & ,y\r ,_w      
,,0-#jjb ,a ,bibliography ( ,basic      

,books on ,atomic ,en]gy    ,,0-#jjd    
,comput]s    ,,0-#jjh ,electricity &    
,man    ,,0-#jjf ,nucle> ,t]ms1 ,a      
,gloss>y    ,,0-#jac ,secrets ( ! ,pa/3 
,nucle> ,en]gy ,applications 9 ,art &   
,ar*aeology      ,! ,environm5t         
,,0-#dad ,nature's ,invisible ,rays     
,,0-#bjd ,nucle> ,p[] & ! ,environm5t   
,biology      ,,0-#ajb ,atoms 9         
,agriculture    ,,0-#aje ,! ,g5etic     
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,y\r ,body & ,radiation      ,physics   
,,0-#dja ,accel]ators    ,,0-#djc       
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,,0-#djf ,las]s    ,,0-#djg             
,micro/ructure ( ,matt]    ,,0-#daa ,p[]
 f ,radioisotopes      ,*emi/ry         
,,0-#cjc ,! ,atomic ,f+]pr9t3 ,neutron  
,activation ,analysis    ,,0-#cjb       
,cryog5ics1 ,! ,uncommon ,cold          
,,0-#cjf ,radioisotopes 9 ,indu/ry      
,nucle> ,reactors      ,,0-#ejb ,atomic 

,p[] ,safety    ,,0-#eac ,bre$]         
,reactors    ,,0-#ejc ,! ,fir/ ,reactor 
,,0-#eje ,nucle> ,p[] ,plants           
,,0-#ejg ,nucle> ,reactors    ,,0-#ejh  
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,comm5ts are invit$ reg>d+ ?is booklet &
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,u4 ,s4 ,,atomic ,,en]gy ,,commission   
,(fice ( ,in=mation ,s]vices            
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publication in=mation f ! pr9t$ edition3
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c\ntry ( publication4    --,"s captions 
describ+ sep>ately plac$ images 7 split1
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illu/rations 9 all ?ree    volumes3     
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function on local copies ( ! files4