6 JOURNAL OF THE 
position. Probably basic oxalates with many different 
ratios between the oxalate and the hydroxide might be 
secured. On drying at 100°, or even a little lower, the 
oxalic acid is gradually volatilized and lost. This is true 
of all the oxalates and double oxalates prepared so that. 
the only mode of drying these preparations was between 
filter paper. 
The Acid Oxalate Prepared by Crystallization.—In 
preparing this oxalate, zirconium hydroxide was dissolved 
in oxalic acid. The hydroxide is quite soluble in oxalic 
acid, and aconcentrated solution is readily obtained. <A 
considerable excess cf the acid is required to hold the oxa- 
late thus formed in solution. If this solution be acidified 
by means of hydrochloric acid a very fine precipitate is 
obtained settling very slowly, easily passing through the 
best filter papers and insoluble even in a considerable 
excess of the acid, but soluble in concentrated sulphuric 
acid. ‘This precipitate was not analyzed, nor were the 
exact conditions of its formation determined, as its exam- 
ination did not promise results of sufficient importance to 
justify overcoming the difficulties in the way. 
Onevaporating the acid solution of the oxalate the excess 
of oxalic acia first crystallized out. In the various prep- 
arations made, the first one or two crops of long crystals 
were found to be nearly pure oxalic acid, and were rejected. 
Th n the form of the crystals changed to small granular 
or prismatic masses, and with each succeeding crop of 
crystals the percentage of zirconium increased, reaching — 
speedily an approximately constant ratio. No difference 
in the form of the crystals in these different crops could 
be detected on superficial examination, and hence it was 
impossible to distinguish between the zirconium oxalate 
and the oxalic acid almost free of zirconium, except by 
analysis. In no case was the normal oxalate secured. 
The analyses showed a tendency toward the formation of 
an acid oxalate and to mixtures of this with the normal 
oxalate. These mixtures were gotten in the later crys- 
