697 



curve approaches more and more the axis of the zero-value. The 

 dispersion has therefore, properly speaking, only a really "normal" 

 character between 6240 A.LT,, and 6400 A.U. The maximum of the 

 laevogyratory rotation is situated at about 6000 A.U. 



On comparing the magnitude of the rotations for corresponding 

 wave-lengths, in the cases of the complex o.mlates of chromiuin, 

 cobaltum, rhodium, and iridium, — the intluence of the specific nature 

 of the central metallic atom on the whole cliaracter, as well as on the 

 absolute values of the rotation, is immediately evident. The figures 2 

 and 3 will show this clearly ; in tig. 2 the curves of tlie cobalti-, 

 rhodium- and iridium-Ha.\is are drawn, in fig. 3 those of the c/^rowmyn-, 

 and cobalti-sedis. While the complex rhodium-, and iridium-oxalates 

 show an analogous dispersion, the cohalti-s&it seems to have a 



//l<>/m//a/ 7lr/r///(Vf 



«00 'tSOO «00 JOOO 5100 5200 5300 5M0 5500 5600 5?00 5800 5900 6000 6100 6200 6300 SMO KOO 6600 bWO 6800 WOO 7000 fi/u/J/i /// ■ '///i//s _ 



Fig. 2. 



