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SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 54 



Weibull/ following Berzelius, ignited the sulphate, and also made a 

 similar set of experiments with the selenate of zirconium, obtaining re- 

 sults as follows: 



Sulphate. Zr(_S0t)2. 



Mean, 43.150, ± .0207 



Hence Zr = 89.54. 



Selenate. ZriSeOJ.. 



1.0212 grm. salt gave 

 .8418 

 .6035 

 .8793 

 .3089 



.3323 ZrOj. 

 .2744 " 

 .1964 " 

 .2870 " 

 .1003 " 



32.540 per cent. 



32.597 



32.544 



32.640 



32.470 



Mean, 32.558, ± .0192 



Hence Zr= 90.79. 



Bailey" also ignited the sulphate, after careful investigation of his 

 material, and of the conditions needful to ensure success. He found that 

 the salt was perfectly stable at 400°, while every trace of free sulphuric 

 acid was expelled at 350°. The chief difficulty in the process arises from 

 the fact that the zirconia produced by the ignition is very light, and 

 easily carried off mechanically, so that the percentage found is likely to 

 be too low. This difficulty was avoided by the use of a double crucible, 

 the outer one retaining particles of zirconia which otherwise might be 

 lost. The results, corrected for buoyancy of the air, are as follows : 



' Lund. Araskrift, Vol. IS. ]881-'82. 



* Proc. Roy. Soc, 46, 74. Chem. News, 60, 32. 



