276 PEKSONAL PREPARATION FOR RESEARCH. 



his death, in 1851. His great discovery of electro-mag- 

 netism was made in 1819. Sir H. Davy was born in 

 1778. The publication of his discoveries was commenced 

 when he was about twenty years of age, and was con- 

 tinued until 1829, the year of his death. The discoveries 

 of the great Swedish chemist Berzelius were exceedingly 

 numerous; they were commenced in 1806, when he was 

 twenty-eight years of age, and continued until he died, in 

 1848. 



Faraday's researches were commenced in 1816, when 

 he was twenty-five years of age, and continued till 1862 ; 

 his memory then failed him, and he made no more dis- 

 coveries : he died in 1867. A complete list of all the 

 published researches, English and foreign, made since 

 the year 1800, of every scientific investigator, may be 

 found in the ' Eoyal Society Catalogue of Scientific 

 Papers.' 



6 Some of the greatest men who have ever lived have 

 either died early, or might have done so for their fame. 

 Newton himself had completed many of his grand dis- 

 coveries, and laid the foundation of all of them, before he 

 had reached his twenty-fifth year ; and, although he lived 

 to a great age, may be said to have finished all that was 

 brilliant in his career at the early period of forty-five. 

 After this, it has been remarked, that he wrote nothing, 

 except some further explanations and developments of 

 what he had previously published. But to go to other 

 great names : James Gregory, the celebrated inventor of 

 the reflecting telescope, was suddenly struck blind in his 

 thirty-seventh year, while observing the satellites of Jypiter, 

 and died a few days after. Torricelli, whose famous dis- 

 covery of the barometer we have already mentioned, and 

 who had deservedly acquired the reputation of being in 



