397 



rotation of any iiieniber of' tlie series. Tliis residue must represent 

 tiie value for 2 H, since Cu//n„_|_o— // CH.^ = 2 //. Hence we 

 may write 2//^ 0.508 or the value of liydrogen as 0.254. Then 

 again, it is Icnown that CZ/j = J .023, wiience by deducting tlie value 

 of 2// we may obtain tlie value for carbon = 0.5i 5. Again, when 

 hydi'Ogen is removed from a compound and replaced by chlorine, 

 there is an increase in rotatory power of 1.480; hence the value 

 for ciilorine may be assumed to be 1.480 f 0.254 = 1.734. Similarly, 

 bromine and iodine may i»e calculated to be equivalent to 3.562 

 and 7.757 respectively. 



It has been found out that molecular magnetic rotation of elements 

 is also a periodic function of their atomic weights. 



-^ Atomic weights of elements 

 l''ig. 6. 



The curve is obtained from the following data (see table p. 436) 

 collected from the works of ditferent investigators. 



