PouiitoK— On the Extraction of Glucinum from Beryl. 145 
precipitated the remainder of the alum, leaving only the glucina and iron in 
solution. After distilling off the alcohol, the iron and glucina were separated as 
before. | 
A preliminary experiment on about 1000 grams of beryl also yielded a 
quantity of crude glucinum basic carbonate; but as it was of an experimental 
character, and substantially the same as the first process described, it is not 
necessary to give details farther than to say that the oxides were precipitated in 
two fractions by ammonia; and nothing was gained by this, as the alumina and 
elucina came down in much the same ratio in both fractions. Fractional precipi- 
tation with carbonate of soda also failed to separate the two bases. Probably the 
best means of extraction would be to fuse the beryl with caustic potash in place 
of soda, then to treat direct with sulphuric acid, filter off the silica, and crystallize 
out the alum, and then use carbonate of ammonia, thus avoiding the precipitation 
by ammonia. This is not easily done in the case of fusion with caustic soda, 
owing to the great solubility of soda alum. 
There was a good deal of loss in the various processes of extraction, part of 
the glucina evidently crystallizing out with the alum and aluminium chloride, for 
the yield was below that shown by analysis. 
V. QUANTITATIVE SEPARATION OF ALUMINIUM AND GLUCINUM. 
None of the methods described for the separation of glucinum and aluminium 
were found very convenient in practice. Fusion with acid potassium fluoride and 
solution with hydrofluoric acid, as described in Fresenius, are said to give the most 
accurate and reliable results. I found, however, that the following modification 
of this process is much more convenient in practice, especially as it can be applied 
direct to a mixed precipitate of alumina and glucina, in the platinum crucible in 
which it has been ignited and weighed. 
To one gram or less of the ignited oxides, or dry hydrates, or carbonates, add 
10 cc. of hydrofluoric acid; then dilute in a platinum basin by the addition of 
not less than 250 ce. of distilled water, and add 20 ce. of a strong solution of acid 
fluoride of potassium. Any alumina present at once precipitates as the double 
fluoride AlF,2KF ; and is filtered off in the cold, using a vulcanite or platinum 
funnel. If one is short of platinum basins, a beaker lined with a little paraftin 
wax will do to catch the filtrate and washings. After washing, the precipitate is 
dried, removed from the paper, the paper burned, and then the precipitate added 
to the crucible and heated to redness for a moment, when fairly accurate results 
are obtained. If rigorous accuracy is required, the precipitate must be decom- 
posed by strong sulphuric acid, heated until fumes of sulphuric acid are coming 
off freely to drive off all the hydrofluoric acid, then dissolved, and the alumina 
