1877.] Mr. G. Williams on Emeralds mid Beryls. 173 



Experiment I. — A mixture was taken of 0-5000 gramme of glucina 

 and the same amount of alumina ; after three treatments for forty-eight 

 hours each with carbonate of ammonium the following results were 

 obtained. The residue of alumina weighed 0*5107 gramme. 



'No. of extractions. Glucina obtained. 



I. 0-3896 



H 0-0739 



III 0-0203 



0-4838 



Composition of Obtained in three 



mixture. treatments. 



Glucina . .50-00 48-38 



Alumina . . 50-00 51-07 



100-00 99-45 



Experiment II. — Upon a similar mixture the following modification of 

 the process was tried. The mixture was dissolved in hydrochloric acid, 

 the excess of acid was neutralized with ammonia, and 200 cub. centims . 

 of a warm solution of ammonium carbonate were added. The solution 

 was stirred briskly for five minutes, and then filtered on rapidly. The 

 precipitate was only washed moderately so as not to dilute the nitrate 

 too much. The filtrate was allowed to stand for twenty-four hours, the 

 deposit was filtered oh 5 , added to the first residue, dissolved with it in 

 hydrochloric acid, and again treated twice with 100 cub. centims. of 

 carbonate-of-ammonium solution in the cold for twenty-four hours each 

 time. The alumina weighed 0-5201 gramme. 



"No. of extractions. Glucina obtained. 



1 0-4450 



II 0-0163 



III . . 0-0161 



0-4774 



Composition of Obtained in three 



mixture. treatments. 



Glucina ..50-00 47'74 



Alumina . .50-00 52-01 



100-00 99-75 



Experiment III. — A mixture was then prepared of 0*2640 gramme of 

 glucina and 0*8520 gramme of alumina. It was dissolved in hydrochloric 

 acid, neutralized with carbonate of ammonium, and digested with 

 95 cub. centims. of the carbonate-of-ammonium solution for twenty-four 

 hours ; it was stirred occasionally. The solution was then filtered, the 

 residue dissolved in hydrochloric acid, and, after neutralizing, was treated 



