Made of Lancaster. 61 



The mass was completely fused, and being softened with 

 water, was entirely dissolved in dilute muriatic acid. 

 The solution was now evaporated to dryness and heated 

 to render the silicic acid insoluble. The mass was then 

 moistened with muriatic acid, and the soluble muriates 

 dissolved in water, leaving the silicic acid, which, col- 

 lected on a filter, washed, dried and ignited, weighed 



sixteen grains. 



Process J). The solution and washes were reduced 

 in bulk by evaporation, and then treated vnXh a solution 

 of carbonate of ammonia in excess, to precipitate the 

 alumina. The whole was then thrown on a filter of 

 knowTi weight, and the alumina separated by the filter 

 was thoroughly washed with hot water for tlurty-six 



away pure. The alumina 

 rhed thirty grains. Filter, 



came 



and 



when burned, gave 0.5 gr. alumina to be added to the 



above. 



Process E. The alumina redissolved in sulphuric 



acid left 0.5 gr. silicic acid to be added to that obtained 



by process C. To determine if potash was contained In 



the mineral, I examined the filtered solution and washes, 



by means of the muriate of platma, but found no trace of 



its presence 



This mineral consists then, 



Process 



in 50 parts, or, in 100 parts, 



16.5 33.0 



D, Alumma, 30.5 61.0 



« B, Prot-oxide of iron, 2.0 4.0 



A, Water, ."75 l.» 



loss .25 loss .5 



50.00 100.0 



