ATOMIC WEIGHTS 



489 



In 1865 Delafontaine ' published some results obtained from yttrium 

 sulphate, the yttrium being thrown down as oxalate and weighed as 

 oxide. In the fourth column I give the percentages of Yt^Og reckoned 

 from tlie anhydrous sulphate : 



Mean, 49.998, ± .081 

 Hence Yt = 9G.09. 



In another paper' Delafontaine gives the following percentages of 

 YtoOg in dry sulphate. The mode of estimation was the same as before : 



48.23 

 48.09 

 48.37 



Mean, 48.23, it .055 



Hence Yt= 87.89. 



Bahr and Bunsen/ and likewise Cleve, adopted the method of con- 

 verting dry yttrium oxide into anhydrous sulphate, and noting the gain 

 in weight. Bahr and Bunsen give us the two following results. I add 

 the usual percentage column : 



Mean, 49.2695, ± .0233 

 Hence Yt = 93.64. 



Cleve's first results are published in a joint memoir by Cleve and 

 Hoeglund/ and are as follows : 



0096 



Hence Yt= 89.58. 



' Ann. C'hem. Phann., 134, lOS. 1865. 



2 Arch. Sci. Phys. Nat. (2), 25, 119. 1860. 



3 Ann. Cheni. Phann., 137, 21. 1866. 



* K. Svenska \et. Akad. Handlingar. Rd. 1, No. S. 1S73. 



