Browning and Flint — Complexity of Tellurium. 349 



above each in an inverted position to distribute the heat more 

 evenly. Finally they were removed and ignited for a short 

 time at dull redness until the dioxide had fused to a glassy 

 condition. The weighings were conducted with properly 

 standardized weights, by the method of vibrations, and the 

 usual corrections were applied. The results are recorded in 

 Table I. 



Table I. 



2Te0 2 . HN0 3 Per cent 



taken Te0 2 found Te0 2 



Alpha gram. gram. found 



(1) 0-09575 0-0V986 83'40 



(2) 0-27354 0-22813 83-39 



(3) 0-60237 050272 83'45 



(4) 0-66288 0*55331 83'45 



(5) 1-60542 1-33912 83'41 



(6) 1-78565 1*48982 83'43 

 Beta 



(1) 0-08473 0-07081 83*57 



(2) 0-23125 0-19256 83'63 



(3) 0-87484 0-73306 83'79 



(4) 0-39778 0-33232 83*56 



(5) 0-39479 0-33005 83'60 



The mean percentage of dioxide in alpha (83*42 per cent) 

 gives an atomic weight of 126-53; that for beta (83*63 per 

 cent), 128-97. It is thus apparent that the fractions are not 

 homogeneous with each other, since they had been crystallized 

 under precisely similar conditions, with due precautions to 

 secure constancy of composition in each case, and with exactly 

 similar treatment in the performance of the analyses. 



(2) Analyses made by the permanganate process mentioned 

 above confirmed this difference. The material was dissolved 

 with two cubic centimeters of ten per cent potassium hydrox- 

 ide and the solution was acidified with sulphuric acid (1:1), 

 one cubic centimeter in excess, diluted to one hundred cubic 

 centimeters with water, and treated with an excess of perman- 

 ganate, oxalic acid being then added in excess. The mixture 

 was then warmed nearly to boiling and the excess of oxalic 

 acid determined by permanganate. The titrations were con- 

 ducted in porcelain dishes. The results follow in Table II. 



Computation from the permanganate required for the oxida- 

 tion, in each case, gave a mean of 126*64 for alpha, and 

 128*77 for beta. 



(3) A similar difference was again obtained by the ammonia- 

 acetic acid process already referred to. The basic nitrate was 

 dissolved with two cubic centimeters of hydrochloric acid, the 



