In this century the arts received much attention also, 

 great work being produced in the fields of painting (Tur- 

 ner), literature (Goethe), and music (Beethoven, Chopin, 

 Verdi). The basic arguments for a socialized state were put 

 forward by Marx in about 1860. The diesel engine was in- 

 vented (Diesel, 1893). Photography was successfully em- 

 ployed (Talbot, 1839). And medicine made huge strides 

 forward, firstly with the proof of the germ nature of many 

 diseases stated by Pasteur (c. 1860), and secondly with 

 the discovery of anaesthesia by Morton (1846). 



Finally, mainly in our own century mention must be 

 made of the fundamental advances made in physics: the 

 discoveries of the proton by Rutherford in 1911, and of 

 the neutron by Chadwick in 1932, primary constituent 

 particles of matter; the elucidation of the atomic structure 

 of crystals by Bragg in 1913; the artificial transmutation 

 of elements by Rutherford in 1919; the creation of artifi- 

 cially radioactive isotopes by Curie and Joliot in 1934; the 

 Theory of Relativity, including the calculation of the energy- 

 equivalence of matter, by Einstein in 1915; the foundation 

 of the Quantum Theory by Planck in 1900, and Einstein's 

 particulate explanation of radiation in the photoelectric 

 effect (1905); Bohr's explanation of atomic structure 

 (1913), and Rutherford's proof of the existence of the 

 atomic nucleus (191 1 ); the theoretical discovery of mesons 

 by Yukawa (1935); the study of cosmic rays (Millikan, 

 1922). In chemistry: the complete understanding of the 

 chemical combination of atoms (Pauling, 1939); the de- 

 termination of the chemical structures and the synthesis of 

 many biological compounds including sugars (Fischer, 

 1883 onwards), amino-acids (many workers, c. 1850- 

 1935), and chlorophyll (Strell, Woodward, 1960); much 

 progress towards a detailed knowledge of the structures of 



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