4 LOEWENFELD, Contributions to the History of Science. 



to some extent changed but not so much that the methods 

 of by-gone times, either theoretical or practical, could not 

 be studied and used again with some advantage. 



The value of the study of political history in mental 

 culture is admitted. But how often is history well taught, 

 or rather, how rareh' ? 



It is impossible to understand modern times without 

 a knowledge of the development brought about by the 

 evolution of science, caused, accompanied and followed 

 by the great technical inventions like cheap printing, and 

 the triumph over the powers of nature, especially through 

 the applications of steam and electricity and through the 

 use of chemistry. The history of these developments, 

 which at present is only casually taught, should form the 

 basis from which modern universal history ought to be 

 considered, and should be treated at least as extensively 

 as all the Greek and Roman Wars. If we look around 

 and see which methods are everywhere employed to foster 

 historical studies, we find that in literature and politics 

 the study of documents has proved itself invaluable. 

 Every scrap of paper on which a great king, a great 

 musician or writer, has set his pen is nowadays eagerly 

 collected and forms — at least in many cases — the material 

 not only for biographies but for history itself It is to be 

 regretted that similar methods are so seldom emplo}-ed as 

 far as the history of natural science is concerned. 



I mj^self have tried for some years to forma collection 

 of documents relating to the development of science, a 

 few of which I shall refer to in detail. 



I think I could not commence with a name more 

 interesting to this Society than that of John Dalton. 



The most important of my Dalton manuscripts is the 

 table of atomic weights in Dalton's own handwriting. 

 (See PL I.) The paper is not dated but it bears the 



