324 GREAT MEN OF SCIENCE 



long postponed publication of his results only took place in 

 great brevity and in a hardly accessible place;^ they were 

 therefore ignored for a long time. Only from the year 1900 

 onwards did the important and extraordinary significance 

 of his discoveries become clear to everyone; and they now 

 continue in their effect. ^ 



ROBERT WILHELM BUNSEN {1811-1899) 

 GUSTAV KIRCHHOFF {1824-1887) 



BuNSEN and Kirchhoff, from the days when spectrum analy- 

 sis was a great and new conquest of the human mind, 

 and old Heidelberg was the place sung by poets and singers, 

 are a combination, which, in spite of all that has passed since 

 their time, is still unforgotten, and will always remain so. 

 Two rare men of science came together at the most fruitful 

 time of their lives; they joined forces in the most fortunate 

 manner for the purpose of investigating an entirely new road 

 to the discovery of facts. This road led far beyond the 

 known, and actually - such an event had hardly happened 

 since Newton's time - beyond the earth and the solar system 

 into cosmic space, to the discovery of the material compo- 

 sition (chemical analysis) of the most distant stars, concerning 

 which, until then, only very slight changes of position meas- 

 urable in the telescope were known, all questions of their 



^ Mendel's papers 'Versuche iiber Pflanzenhybriden' appeared in the 

 Verhandlungen des natiirforschenden Vcreins in Briinn, 1866 and 1870; 

 reprinted in Ostwald's Klassiker, 4th Ed., Leipzig, 1923. 



2 See W. Bateson's Mendel's Principles of Heredity, 4th Imp., Cam- 

 bridge, 1930. Mendel's original papers are here translated in full. A 

 well-known small book is Punnett's Mendelism, Cambridge, 1927. 



Letters from Mendel (written between 1866 and 1873) which show 

 with what difficulty his ideas were understood by specialists at the time, 

 and how little, therefore, Darwin's warning quoted above was under- 

 stood, even by those who supposed themselves to be adherents of Dar- 

 win's doctrines (Darwinism), have been published in the Ahhandlungen 

 der Sdchsischen Gesellschaft der Wissenschaften, vol. 51, 1906, p. 187. 



