1875.] 4:21 [Swallow. 



hydric acid, filtered, and the filtrate added to the first filtrate. The 

 columbic acid was then ignited and weighed. It was light yellow 

 while hot, and white when cold. 



The filtrate was evaporated somewhat, boiled with nitric acid and 

 precipitated by ammonia. The filtrate so obtained was evaporated 

 to dryness, ignited, dissolved in the least possible quantity of chlor- 

 hydric acid, and the manganese was then precipitated by ammonia. 

 The magnesia was precipitated as phosphate in the filtrate; it was 

 free from manganese. 



The precipitate by ammonia was dissolved in dilute chlorhydric 

 acid, reprecipitated, and the third time dissolved in slight excess 

 of acid, and oxalate of ammonia added in quantity just sufficient to 

 precipitate. It was allowed to stand twelve hours. The white floc- 

 culent precipitate had then settled to a fine powder and was filtered, 

 washed, dried, ignited, dissolved in chlorhydric acid, and reprecip- 

 itated; this was repeated three times and the filtrates evaporated and 

 tested each time. The weight of the oxides of cerium and yttrium 

 was taken as a check upon the subsequent separation. The chlor- 

 hydric acid solution of the two oxides was treated with a hot sat- 

 urated solution of sulphate of potash and a crystal put in to ensure 

 complete saturation. The whole bulk of the liquid was about 10 c.c. 

 After twelve hours the doublf salt of cerium and potash was 

 filtered off, washed with cold sulphate of potash and. dissolved in 

 water; in the duplicate analysis it was precipitated in the very dilute 

 solution by oxalate of ammonia, and this showed a loss of oxide of 

 cerium ; in the analysis given, the dilute solution was first precipita- 

 ted by ammonia, and this precipitate, well washed, dissolved in chlor- 

 hydric acid, and reprecipitated by oxalate of ammonia, gives the 

 correct per cent, as shown by the check weight. 



There was a small residue insoluble in water and in chlorhydric 

 acid, which in fusing with bisulphate decomposed into a soluble por- 

 tion, which gave all the reaction of cerium, and a white powder, 

 which may have been titanic acid but which gave reaction of columbic 

 acid. This residue was too small to obtain satisfactory results; 

 it was about 1 per cent, of the mineral. The solution of yttria in 

 sulphate of potash was diluted, precipitated by oxalate of ammonia, 

 ignited and weighed. The filtrate from the precipitated oxalates of 

 cerium and yttrium was just neutralized with ammonia, boiled, and 

 carbonate of ammonia added. After twelve hours the solution of 

 uranium was filtered off, evaporated to a small bulk and precip- 



