50 On the Refraction-Equivalents of the Elements. [June 17, 



different equivalents are indicated. Thus iron has one value in the ferrous 

 and another in the ferric salts ; and the more highly oxidized compounds 

 of sulphur, phosphorus, arsenic, and nitrogen give different numbers from 

 those given by their simpler combinations. The refraction-equivalent of 

 potassium is estimated from a variety of sources, and the number thus 

 arrived at is employed for the calculation of the other metals that give 

 soluble salts, and for the radicals with which they are combined. 



The following Table gives the general results of these deductions : — 



Element. 



Atomic 



Refraction-equivalent. 



Specific refractive 





weight. 





energy. 





27-4 



8-4 



0-307 





122 



24-5? 



0-201 ? 





75 



15 - 4 (other values?) 



0-205 





137 



15-8 



0115 





11 



4-0 



0-364 





80 



15-3 In dissolved salts 16*9 



0191 or 0-211 





112 



13-6 



0121 





133 



13-7? 



0103? 





40 



10-4 



0-260 





12 



50 



0-417 





92 



13-6? 



0148? 





35-5 



9-9 In dissolved salts 107 



0-279 or 0-301 





52-2 



15-9 In chromates 23 ? 



0-305 or 0-441 ? 



Cobalt 



58-8 



10-8 



0-184 





63-4 



11-6 



0-183 





96 



12-8? 



0133 ? 





19 



1-4? 



0073 ? 



Gold 



197 



240? 



0-122? 





1 



1-3 In hydracids 3 5 



1-3 or 3-5 





127 



24*5 In dissolved salts 27 "2 



0-193 or 0-214 





56 



12-0 In ferric salts 20" 1 



0-214 or 0 359 





207 



24-8 



0-120 





7 



3-8 



0-543 





24 



7-0 



0-292 





55 



12-2 In permanganate 26 2 ? 



0-222 or 0-476? 





200 



20-2? 



0-101 ? 



Nickel 



58-8 



10-4 



0-177 





14 



4-1 In high oxides 53 



0-293 or 0-379 





16 



2-9 



0181 





106-5 



22-4? 



0-210 ? 





31 



18-3 (other values ?) 



0-590 





197-4 



26-0 



0-132 





39-1 



8-1 



0-207 





104-4 



24-2? 



0-232 ? 





85-4 



140 



0-164 





28 



7*5 ? In silicates 6-8 



0-268? or 0-243 





108 



15-7? 



0-145? 





23 



4-8 



0-209 





87-5 



13-6 



0155 





32 



16-0 (other values?) 



0-500 



Thallium 



204 



21-6? 



0106? 



Tin 



118 



19-2? 



0-163 ? 





50 



25-5 ? 



0510? 





51-2 



25-3? 



0-494 ? 





65-2 



10-2 



0-156 





89-6 



210? 



0 234 ? 



