JOURNAL 



OF THE 



Elisha Mitchell Scientific Society. 



THE PRESENT POSITION OF THE PERIODIC 



SYSTEM. 



The atomic theory, (first announced by Dalton in 1803) 

 has for nearly a century formed the basis of Chemistry 

 as a science. It is still the only plausible explanation 

 of the vast array of facts gathered by chemists of all ages 

 and forms the web and woof of all modern chemical the- 

 ories. It has been the object of prolonged discussion and 

 attack, but having withstood the storms of nearly a hun- 

 dred years, its acceptance now is full and it has become so 

 ingrained into the chemist's conception of his science that 

 he looks upon it almost as one of his facts, a foundation 

 stone of his building and seldom stops to realize that 

 after all it is only an assumption, an hypothesis, a theory. 

 To shake it would sadly disturb the fabric of his science. 



A little more than twenty-five years ago with the an- 

 nouncement of the Periodic Law by Mendeleeff this 

 atomic theory reached its highest development and gave its 

 clearest promise of finally leading up to the solution of 

 the true nature of matter. Like the original theory, this 

 development of it received but tardy recognition but the 

 sense of its importance has grown until it stands to-day 

 the central fact of chemistry. Through it new zest has 

 been given to research in fields from which it was thought 

 the harvest had been gathered. It has given a new 

 object to the chemist's work. It systematizes and arran- 

 ges all the facts which he gathers. It gives a compact- 

 ness and symmetry to his science unknown before. It 

 brings a step nearer the realization of that dream of the 



