396 SCIENTIFIC THOUGHT. 



in the early years of the century fixed the task of chemists 

 for a long time ahead. 



To begin with, an enormous amount of work had to 



be done in determining the actual proportions in which 



elementary substances combine. A very large share of 



9. this work belongs to Berzelius, who by a great number 



Berzelius. 



of very accurate determinations confirmed inductively 

 the correctness of Dalton's theory. And even more im- 

 portant than the conformation of the theory was the great 

 harvest of actual knowledge of the things and processes 

 of nature which was collaterally gathered, whilst chemists 

 were trying to prove or to refute existing opinions. 



Indeed, whilst the atomic theory of Dalton was the 

 first step towards a systematic and comprehensive study 

 of chemical phenomena i.e., of the qualitative varieties 

 under which matter presents itself to us on the surface 

 of this globe the extension which was gained in the 

 domain of actual facts was much greater than the simpli- 

 fication which the theory had attempted to give. The 

 number of elements or simple bodies, which in Lavoisier's 

 time hardly exceeded thirty, increased before the year 

 1830 to more than double : the number of new compounds, 

 unknown before, has probably never been counted. Com- 

 pared with this growth of actual knowledge of facts, the 

 development of the theory was slow and uncertain. The 

 view of nature from the atomic point of view marks 

 indeed a great contrast to that from the astronomical 

 ip. point of view. "We now live about as long after the 

 theory and reform of chemistiT through Lavoisier and Dalton as 



gravitation 



compared. Laplace lived after the reform of physical astronomy 



