302 Mr Connell on the Chemical ConstUuticm c)f Gadolinita. 



red heat. This ignited matter, of course, was the yttria in a 

 state of purity, or combined with glucina, if the mineral contained 

 that earth. The most obvious method of investigating this 

 latter point was to redissolve the ignited matter in muriatic acid, 

 and treat the solution with caustic potash ; and in this way I was 

 enabled to detect glucina in the mineral. I found, however, 

 that, from the much greater relative quantity of yttria, this process 

 was extremely imperfect ; and the method, therefore, which I 

 adopted was, in the first place, to throw down as much of the yttria 

 as possible from the muriatic solution, by means of oxalic acid, 

 after nearly neutralizing it by ammonia. The oxalate of yttria 

 was then separated by filtration ; the remaining liquid precipi- 

 tated by ammonia ; and the precipitate boiled with caustic pot- 

 ash, and then filtered from the undissolved matter. From the 

 alkaline solution a gelatinous substance was obtained by super- 

 saturation with muriatic acid, and precipitation by ammonia, 

 which was found to be soluble in carbonate of ammonia, and to 

 give with nitrate of cobalt, before the blowpipe, a black or dark 

 grey glass ; and, in short, to have all the properties of hydrate 

 of glucina. The matter left undissolved by the alkaline ley, was 

 once more dissolved in acid, and treated with caustic potash, to 

 complete the separation of the glucina from the small quantity of 

 yttria which had not been thrown down by the oxalic acid. 



In the principal analysis, with the view of diminishing the 

 great tediousness of the incineration of the yttria and glucina, 

 oxalic acid was employed to precipitate as much yttria as pos- 

 sible, before separating the iron ; and the iron was then obtain- 

 ed as before, by precipitating by ammonia, redissolving the pre- 

 cipitate, and then employing the method of tartaric acid, and 

 hydrosulphuret of ammonia. The glucina and remaining yttria 

 were then separated as formerly. But although in this way there 

 is much less matter to incinerate, the other method appears to 

 be'preferable in other respects. 



By adding oxalate of ammonia to the liquid from which the 

 yttria, glucina, and oxide of iron had been originally separated 

 together, a minute quantity of lime was obtained. 



By the process of which the above detail offers a general out- 

 line, I obtained from the above-mentioned portion of the speci- 

 men marked as from Fahlun, the following constituents: — 



