Photo: Rischgitz Collection. 



JOHN DALTON (1766-1844) 



One of the greatest of British chemists, the son of a Quaker 

 weaver, famous for his development of the Atomic Theory. He 

 maintained that atoms are minute particles of matter which 

 cannot be further subdivided; that atoms of the same element 

 are all alike and of equal weight, while those of different ele- 

 ments are unlike; and that compounds are formed by the union 

 of atoms of different elements in simple numerical proportions. 

 Dalton also made very important physical researches on gases 

 and vapours. He was a scientific discoverer of the first order. 

 He "never found time" to marry. 



Photo: Henri Manuel. 



MME. SKLODOWSKI CURIE 



Along with her husband, M. Pierre Curie, Professor in Paris, 

 Madame Curie discovered Radium. From pitchblende they 

 extracted radium chloride. Radium is present in pitchblende in 

 very minute quantity, not more than one part in five or ten 

 million of the mineral. Mme. Curie went on to establish the 

 atomic weight of radium (226) and to make further discoveries 

 of lasting importance. 



Photo: Russell, London. 



PROFESSOR FREDERICK SODDY ONE OF THE MOST 



BRILLIANT OF PRESENT-DAY CHEMISTS 



He has made great contributions to physical chemistry, 

 notably in connection with radio-activity. He was trained 

 under Sir William Ramsay and Sir Ernest Rutherford and 

 has shared in their discoveries. He is one of the professors of 

 chemistry in the University of Oxford, and besides being a 

 distinguished maker of new knowledge is widely concerned 

 with what Bacon called "the relief of man's estate." 



M:CHAKL FARADAY (1791-1867) 



One of the greatest men of science that England has pro- 

 duced. The son of a journeyman blacksmith, he became in 

 1813 assistant to Sir Humphry Davy at the Royal Institution 

 and remained at work there, experimenting and lecturing, for 

 over fifty years. He had a very wonderful mind and a singu- 

 larly attractive character. His researches on gases and their 

 condensation, on electricity, magnetism, and electro-magnet- 

 ism are of the first importance, and a monument to genius of 

 the highest order. Everyone knows his Chemical History of 

 a Candle. 



