,ell5 ,s4 ,ri*>ds ,monographs ,no4 #b   
,publi%$ by ,vass> ,college             
,! ,discov]y                            
(                                       
,radium      ,x is my e>ne/ desire t "s 
( y %all c>ry on ?is sci5tific  "w & w  
keep = y\r ambition ! det]m9ation to    
make a  p]man5t contribution to sci5ce  
,m4 ,curie                              
,address by                             
,madame ,m4 ,curie                      
at ,vass> ,college                      
,may #ad1 #aiba        ,illu/ration3    
,autograph                              
,,prefatory ,,note      ,9 h] rec5t     
visit to ,am]ica1 ,madame ,curie conf]r$
 a special honor  ^u ,vass> ,college by 
deliv]+ 9 ! *apel on ! ev5+ ( ,may      
f\rte5? ! only ext5d$ address :i* %e    
made 9 ?is c\ntry4 ,9  a simple1        
/raight=w>d way %e told ! /ory ( h]     
great  a*ievem5t4 ,"o realiz$ h[1       
closely environ$ by all ! great         
realities ( human exp]i5ce1 9 ! face (  
trem5d\s difficulties  & ) limit$       

res\rces1 %e _h pursu$ undaunt$ h] se>* 
=  tru?4    ,! discov]y ( radium gave   
,madame ,curie imm$iate di/9ction among 
sci5ti/s on acc\nt ( ! extremely        
significant contribution %e  !reby made 
to ! great ultimate problem ( physical  
sci5ce1 !  con/itution ( matt]4 ,! /rik+
 prop]ties possess$ by radium gave  to  
its discov]y a _w-wide int]e/1 all ! m  
int5se because (  ! hope :i* 0 inspir$  
by ! possible heal+ qualities ( !       
radiations f ?is new elem5t4    ,t hope 
is be+ realiz$ 9 l>ge measure4 ,x is    
!re=e fitt+  t ?is address %\ld h be5   
giv5 by ,madame ,curie at ,vass> &  t x 
%\ld n[ be circulat$ among ! memb]s ( ! 
college "u  ! f\ndation 9 memory ( ,ell5
 ,s4 ,ri*>ds1 :o devot$ h] life to  !   
public heal?4                           
,edna ,c>t]                             
,*airman ( ! ,dep>tm5t ( ,physics4      
,,! ,,discov]y ,,( ,,radium      ,i c\ld
 tell y _m ?+s ab\t radium &            
radioactivity & x w\ld  take a long "t4 
,b z we c n d t1 ,i %all only give y a  

%ort acc\nt ( my e>ly "w ab\t radium4   
,radium is no m a baby1  x is m ?an     
tw5ty ye>s old1 b ! conditions ( !      
discov]y  7 some:at peculi>1 & s x is   
always ( int]e/ to rememb] !m  & to     
expla9 !m4    ,we mu/ g back to ! ye>   
#ahig4 ,pr(essor ,curie & ,i work$ at t 
"t 9 ! laboratory ( ! s*ool ( ,physics &
 ,*emi/ry :]e  ,pr(essor ,curie held 8  
lectures4 ,i 0 engag$ 9 "s "w on uranium
  rays :i* _h be5 discov]$ two ye>s be=e
 by ,pr(essor ,becqu]el4  ,i %all tell y
 h[ ^! uranium rays may be detect$4 ,if 
y take a  photographic plate & wrap x 9 
black pap] & !n on ?is plate1  protect$ 
f ord9>y light1 put "s uranium salt &   
leave x a day1  & ! next day ! plate is 
develop$1 y notice on ! plate a black   
spot at ! place :]e ! uranium salt 04   
,?is spot has be5 made by  special rays 
:i* are giv5 out by ! uranium & are able
 to make an  impression on ! plate 9 !  
same way z ord9>y light4 ,y c also  te/ 
^? rays 9 ano!r way1 by plac+ !m on an  
electroscope4 ,y  "k :at an electroscope

 is4 ,if y *>ge x1 y c keep x *>g$      
sev]al h\rs & m1 unless uranium salts   
are plac$ ne> to x4 ,b  if ?is is ! case
 ! electroscope loses its *>ge & ! gold 
or  alum9um leaf falls gradually 9 a    
progressive way4 ,! spe$ ) :i*  ! leaf  
moves may be us$ z a measure ( !        
int5sity ( ! rays2  ! great] ! spe$1 !  
great] ! int5sity4    ,i sp5t "s "t 9   
/udy+ ! way ( mak+ good measurem5ts ( ! 
uranium rays1 & !n ,i want$ to "k if !re
 7 o!r elem5ts1  giv+ out rays ( ! same 
k9d4 ,s ,i took up a "w ab\t all kn[n   
elem5ts1 & _! comp\nds & f\nd t uranium 
comp\nds are  active & also all ?orium  
comp\nds1 b o!r elem5ts 7 n f\nd        
active1 nor 7 _! comp\nds4 ,z = !       
uranium & ?orium  comp\nds1 ,i f\nd t !y
 7 active 9 proportion to _! uranium  or
 ?orium cont5t4 ,! m uranium or ?orium1 
! great] !  activity1 ! activity be+ an 
atomic prop]ty ( ! elem5ts1 uranium  &  
?orium4    ,!n ,i took up measurem5ts ( 
m9]als & ,i f\nd t sev]al (  ^? :i*     
conta9 uranium or ?orium or bo? 7       

active4 ,b !n !  activity 0 n :at ,i    
c\ld expect1 x 0 great] ?an = uranium or
  ?orium comp\nds l ! oxides :i* are    
almo/ entirely compos$ (  ^! elem5ts4   
,!n ,i ?\ght t !re %\ld be 9 ! m9]als "s
  unkn[n elem5t hav+ a mu* great]       
radioactivity ?an uranium or  ?orium4 ,&
 ,i want$ to f9d & to sep>ate t elem5t1 
& ,i  settl$ to t "w ) ,pr(essor ,curie4
 ,we ?\ght x w\ld be done  9 sev]al     
weeks or mon?s1 b x 0 n s4 ,x took _m   
ye>s (  h>d "w to f9i% t task4 ,!re 0 n 
"o new elem5t1 !re 7  sev]al ( !m4 ,b ! 
mo/ important is radium :i* c\ld be     
sep>at$ 9 a pure /ate4    ,all ! te/s = 
! sep>ation 7 done by ! me?od (         
electrical  measurem5ts ) "s k9d (      
electroscope4 ,we j _h to make  *emical 
sep>ations & to exam9e all products     
obta9$ ) respect  to _! activity4 ,!    
product :i* reta9$ ! radioactivity 0    
consid]$ z t "o :i* _h kept ! new       
elem5t2 &1 z !  radioactivity 0 m /rong 
9 "s products1 we knew t we _h  succe$$ 
9 conc5trat+ ! new elem5t4 ,!           

radioactivity 0 us$  9 ! same way z a   
spectroscopical te/4    ,! difficulty 0 
t !re is n mu* radium 9 a m9]al2 ?is we 
did n "k at ! beg9n+4 ,b we n[ "k t !re 
is n ev5  "o "p ( radium 9 a million    
p>ts ( good ore4 ,& too1 to get a  small
 quantity ( pure radium salt1 "o is     
oblig$ to "w up a huge  quantity ( ore4 
,& t 0 v h>d 9 a laboratory4    ,we _h n
 ev5 a good laboratory at t "t4 ,we     
work$ 9 a hang>  :]e !re 7 no           
improvem5ts1 no good *emical            
arrangem5ts4 ,we _h  no help1 no money4 
,& because ( t ! "w c\ld n g on z x     
w\ld h done "u bett] conditions4 ,i did 
myself ! num]\s  cry/alizations :i* 7   
want$ to get ! radium salt sep>at$ f  ! 
b>ium salt ) :i* x is obta9$ out ( !    
ore4 ,& 9 #aijb ,i  f9ally succe$$ 9    
gett+ pure radium *loride & det]m9+ !   
atomic weight ( ! new elem5t radium1 :i*
 is #bbf :ile t (  b>ium is only #acg4  
,lat] ,i c\ld also sep>ate ! metal      
radium1 b t 0 a v  difficult "w2 &1 z x 
is n necess>y = ! use ( radium to  h x 9

 ?is /ate1 x is n g5]ally prep>$ t way4 
,n[1 ! special int]e/ ( radium is 9 !   
int5sity ( its rays  :i* is sev]al      
million times great] ?an ! uranium rays4
 ,& !  effects ( ! rays make ! radium s 
important4 ,if we take a practical  po9t
 ( view1 !n ! mo/ important prop]ty ( ! 
rays is !  production ( physiological   
effects on ! cells ( ! human organism4  
,^! effects may be us$ = ! cure ( sev]al
 diseases4 ,good results  h be5 obta9$ 9
 _m cases4 ,:at is consid]$ p>ticul>ly  
important is ! treatm5t ( canc]4 ,!     
m$ical utilization ( radium  makes x    
necess>y to get t elem5t 9 suffici5t    
quantities4 ,& s  a factory ( radium 0  
/>t$ to beg9 ) 9 ,france1 & lat] 9      
,am]ica :]e a big quantity ( ore nam$   
c>notite is available4  ,am]ica does    
produce _m grams ( radium e ye> b !     
price is  /ill v high because ! quantity
 ( radium conta9$ 9 ! ore is  s small4  
,! radium is m ?an a hundr$ ?\s& times  
de>] ?an  gold4    ,b we mu/ n =get t :5
 radium 0 discov]$ no "o knew t  x w\ld 

prove useful 9 hospitals4 ,! "w 0 "o (  
pure sci5ce4  ,& ?is is a pro( t        
sci5tific "w mu/ n be consid]$ f !  po9t
 ( view ( ! direct usefulness ( x4 ,x   
mu/ be done =  itself1 = ! beauty (     
sci5ce1 & !n !re is always ! *ance  t a 
sci5tific discov]y may become l ! radium
 a b5efit =  humanity4    ,b sci5ce is n
 ri*1 x does n dispose ( important      
means1 x does  n g5]ally meet           
recognition be=e ! mat]ial usefulness ( 
x has  be5 prov$4 ,! factories produce  
_m grams ( radium e ye>1 b  !           
laboratories h v small quantities4 ,x is
 ! same = my  laboratory & ,i am v      
grateful to ! ,am]ican wom5 :o wi% me to
  h m ( radium & give me ! opportunity (
 do+ m "w )  x4    ,! sci5tific hi/ory (
 radium is beautiful4 ,! prop]ties ( !  
rays h be5 /udi$ v closely4 ,we "k t    
p>ticles are expell$  f radium ) a v    
great velocity ne> to t ( ! light4 ,we  
"k t ! atoms ( radium are de/roy$ by    
expulsion ( ^!  p>ticles1 "s ( :i* are  
atoms ( helium4 ,& 9 t way x has  be5   

prov$ t ! radioactive elem5ts are       
con/antly dis9tegrat+  & t !y produce at
 ! end ord9>y elem5ts1 pr9cipally helium
  & lead4 ,t is1 z y see1 a !ory (      
trans=mation ( atoms :i*  are n /able1 z
 0 believ$ be=e1 b may und]go spontane\s
  *anges4    ,radium is n alone 9 hav+  
^! prop]ties4 ,_m hav+ o!r  radioelem5ts
 are kn[n already1 ! polonium1 !        
meso?orium1 !  radio?orium1 ! act9ium4  
,we "k also radioactive gases1 nam$     
emanations4 ,!re is a great v>iety (    
sub/ances & effects 9  radioactivity4   
,!re is always a va/ field left to      
exp]im5tation &  ,i hope t we may h "s  
beautiful progress 9 ! foll[+ ye>s4  ,x 
is my e>ne/ desire t "s ( y %\ld c>ry on
 ?is sci5tific  "w & keep = y\r ambition
 ! det]m9ation to make a p]man5t        
contribution to sci5ce4                 
,m4 ,curie4        ,illu/ration3        
,photograph    ,) my fri5d%ip = !       
,/ud5ts ( ,vass> ,college--             
,m4 ,curie                              
,transcrib]'s ,notes      --,sil5tly    

correct$ a few typos4    --,reta9$      
publication in=mation f ! pr9t$ edition3
 ?is e,book    is public-doma9 9 !      
c\ntry ( publication4    --,g5]at$ cov] 
& sp9e images f elem5ts 9 ! pr9t$       
edition4    --,9 ! text v]sions only1   
text 9 italics is delimit$ by           
und]scores4