THE EVOLUTION OF 

 THE SCIENCES 



THE TENDENCIES OF CHEMISTRY 



ALL the experimental sciences have passed 

 through three successive stages. First comes 

 a long chaotic period, during which the data 

 of observation and experiment float without 

 order or connection in the mass of human know- 

 ledge, the whole forming, as it were, a great 

 nebula which, when the time comes, condenses 

 round separate nuclei. Between the Renais- 

 sance and the end of the eighteenth century 

 the sciences w r ere separating and crystallising 

 out. Each science defined the goal of its re- 

 searches, delimited its domain and organised 

 itself internally by the continual acquisition of 

 new laws. At the present day we are entering 

 on the third stage : the sciences, separate in the 



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