2 jouuNAiy Q-B" the; 



etc., will show on what an imperfect basis the knowl- 

 edg*e of the constitution of these bodies rests. Hiortdahl 

 states that he secured direct union only by ignition with 

 alkaline carbonates. His attempts with the volatile chlor- 

 ides failed. On heating" zirconia with sodium carbonate 

 one equivalent of carbon dioxide was driven out, and it is 

 on the loss of carbon dioxide upon ignition that his figures 

 for the composition of the resulting- products are largely 

 based. On heating equivalent amounts of zirconia and 

 sodium carbonate a crystalline mass was obtained, which 

 slowly absorbed moisture from the air. On treating this 

 with water no decomposition was noted at first, but 

 soon the water became alkaline and zirconia separated. 

 This was taken as proof that the zirconia was decompos- 

 ed by the water. In the experiment 0.3910 gram zirconia 

 heated with 0.3130 g-ram sodium carbonate to a dark red- 

 ness for nine hours lost 0.1310 <>-ram carbon dioxide, and 

 on treatment with water 0.3871 gram "zirconia," or 99.03 

 per cent, was left. If an excess of sodium carbonate is 

 used can one drive out two equivalents of carbon dioxide. 

 A little further down he notes that the "Gewichtsverlust 

 zugleich von der Temperatur und der Dauer des Gliihens 

 abhaugt." These are the determinations from which 

 formulas for the zirconates are worked out. 



It is scarcely necessary to say that for purposes of cal- 

 culation these figures are entirely worthless. The loss 

 of carbon dioxide is due to a partial formation of hydrox- 

 ide as well as to a combination with zirconia. The fused 

 mass of sodium carbonate, h\'droxide, zirconate and un- 

 changed zirconia will of course prove hygroscopic, and 

 water will wash away all except the last two mentioned. 

 We have failed to get any positive evidence that a zircon- 

 ate formed by fusion was decomposed by water or was 

 appreciably soluble in it. ^ 



In his second paper, Hiortdahl treats the fused mass of 

 zirconia and sodium carbonate with water acidified with 

 hydrochloric acid and analyzes the residue, finding in it: 



