ELISHA MITCHELL SCIENTIFIC SOCIETY. 43 
- one successfully carried out in the series, is taken for the 
purpose. 
Weights of zirconium oxychloride: March 28..........5.25910 
“3 a so 3 . i oS ea 5.25786 
+4 % : BOR Ye 58. 2B O 
ie ote ef + Aigerts tdree: 325. east: 5.25762 
Weiehts‘of sircomumoxide April dhs ele 2.78759 
5 a ik of ie ae 7-5 De ee gaa oe arg 2.78724 
FS i de *s pa Eb Rw ee ee a 2.78583 
ee ee se ee ce 15 9.78517 
ef rt ve ‘. Sy Para Arete ees 2.78452 ~ 
Ay i - ‘ 1 ES LEN et he 2.78451 
This zirconia was examined for chlorine in most of the 
analyses and was found to be free from it. In the last 
three experiments reported in the series, the ignited resi- 
due was treated with hydrofluoric acid. Ignition after 
this treatment was very difficult, as the mass was not 
compact and coherent. The finely divided zirconia was 
lost in spite of the most careful treatment. The first was 
lost altogether and the weighing was not carried out. 
The second showed, upon the lid signs of the powdered 
zirconia having been swept out. The total loss of weight, 
however, was less than one milligram. This could read- 
ily be attributed to the zirconia and pointed to the absence 
of silica unless in insignificant traces. 
I think great purity may be claimed for the prepara- 
tions used in the analyses. Crystallizing trom hot hy- 
drochloric acid is apt to remove most known impurities, 
and they were eliminated beyond the possibility of detec- 
tion by the ordinary tests. The analyses were not made 
from the same preparation, but from small quantities 
prepared at different times and some crystallized ten or a 
dozen times more than others, yet no appreciable differ- 
ertce could be detected in the resuljs. That these results 
are not in close accord with one another, is due in part to 
the deliquescence of the chloride and to the risks involved 
in the prolonged heating of the oxide. 
