1835.] Chemical Analysis of Gadolinite y tifc. 411 



by oxalate of ammonia. The oxalate collected on a filter, 

 well washed and ignited, left 12*257 grs. of yttria. The 

 residual liquid, after being mixed with a little nitric acid, 

 was precipitated by chloride of barium. The sulphate 

 of barytes obtained, weighed, after ignition, 32 grs. = 11*03 

 grs. of sulphuric acid. This analysis gives, 



Yttria .... 12*257 or 5*54 

 Sulphuric acid . . 11*030 ,, 5* 

 Water .... 6*700 „ 3*04 



29*987 

 These three analyses, corresponding so closely in the 

 proportion of acid to base, leave little doubt that the atomic 

 weight of the base in this salt is as high as 5*5. If the 

 yttria employed by. Berzelius contained glucina, it will 

 account for his finding it less. Probably the true compo- 

 sition is, Yttria 5*5 



Sulphuric acid . . 5* 

 Water 2*25 



12*75 



To verify this, solutions of 12*75 sulphate of yttria, 8*875 

 oxalate of ammonia were mixed. The residual liquid was 

 neither altered by sulphate of yttria nor oxalate of ammonia. 

 But when the residual liquid was evaporated nearly to dry- 

 ness, it was found to give traces of yttria by prussiate of 

 potash. It was mixed with caustic ammonia, which threw 

 down a small quantity of yttria, weighing 0*32 grs. The 

 oxalate collected on a filter and washed, left, when ignited, 

 5*1 grs. of yttria. 8*875 grs. of oxalate of ammonia, there- 

 fore, do not decompose completely 12*75 grs. of sulphate of 

 yttria. Probably because the oxalate was not quite dry. 

 Solutions of 12*75 grains sulphate of yttria, 

 ,, 20*75 ,, nitrate of lead, 



were mixed. The supernatant liquid was neither affected 

 by sulphate of soda nor nitrate of lead. For greater cer- 

 tainty, it was divided into two portions : into the one was 

 poured nitrate of lead, and into the other sulphate of soda. 

 After standing 24 hours, a mere trace of opacity was per- 

 ceptible at the bottom of the vessel, to which the nitrate 

 of lead had been added. 



