The Experiments of Ramsay 



The Russian chemist Mendeleeff had the 

 good fortune to present this interdependence in a 

 striking form, which has for a long time com- 

 pelled the attention of chemists, and will receive 

 a fresh lease of interest from Ramsay's dis- 

 coveries. If the simple bodies are arranged in 

 the order of their increasing atomic weights, as in 

 the appended table, the properties of the suc- 

 cessive elements are found to present a certain 

 periodicity. The table is divided into rows 

 and columns so as to show this periodicity, and 

 the arrangement is such that the columns corre- 

 spond practically to the natural families already 

 distinguished by chemists. It is true that 

 recourse has been had to the artifice of leaving 

 some of the squares empty, but these gaps may 

 be assumed to correspond to still unknown 

 bodies. In fact the bodies discovered since the 

 publication of Mendeleeff s table have fitted as a 

 matter of course into the empty squares; this 

 occurred in the case of germanium, isolated by 

 Winckler, and of gallium, obtained by Lecoq de 

 Boisbaudran; the inert gases of the atmosphere 

 likewise found a place waiting for them in the 

 table. The work of Mendeleeff is open to many 



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