Prof. Berzelius on Thorina and its Salts. 223 



Art. V. "-^Distinctive properties of Thorina and its Salts, 

 Communicated by the Translator. 



In a former Number (No. ii. New Series, p. 207,) we gave the 

 general properties of this new earth as stated by Berzelius. The 

 following are its distinctive properties, and those of its salts 

 from his paper in the Transactions of the Swedish Academy, 



Thorina is distinguished generally from the other earths by 

 its forming with sulphuric acid a compound, which, by boil- 

 ing, lets fall a white salt, dissolving again, though slowly, on 

 becoming cold. In applying this test, however, it must be re- 

 marked, that this precipitation is prevented by the presence of 

 those bases with which thorina forms double salts, from which, 

 by boiling, no appreciable quantity falls. 



From alumina and glucina it is distinguished by its being 

 insoluble in caustic potash, by which these earths are taken up. 



From yttria, by its forming with sulphate of potash a dou- 

 ble salt insoluble in a saturated solution of sulphate of potash, 

 by which means it may sometimes be separated quantatively 

 from yttria. 



From zirconia by these two circumstances, that zirconia 

 precipitated hot by sulphate of potash, becomes afterwards, in 

 a great degree, insoluble both in water and acids ; and that 

 thorina is precipitated by the cyanide of iron and potassium, 

 by which the salts of zirconia are not troubled. 



From protoxide of cerium by these, — that in drying and 

 heating to redness, it does not assume the colour of the per- 

 oxide of cerium, — and that, before the blowpipe with borax 

 and phosphor-salt, it does not give a coloured glass, either 



of its importance, as one of the most interesting pathological instances of 

 the kind which has yet been published ; and which, from the truly philo- 

 sophical spirit in which it is narrated, he considers as deserving to be 

 ranked with the celebrated case of Nicolai. He conceives that the associa- 

 tion of spectral illusions with that intense state of sympathetic feeling by 

 which an account, for example, of the amputation of an arm will produce 

 an instantaneous and severe sense of pain in the lady's own arm, as a 

 striking feature in the case, and as calculated to throw additional light 

 upon the theory of spectral illusions ; no observations to the same effect 

 having, to his knowledge, been before published. We are promised a few 

 remarks on the subject in a future Number. 



