18 Mr. George on Chloride of Titanium. [Jan. 



Another of the leading corroborations of this theory of the 

 nature of chlorine, it is surely interesting to give, in order to 

 explain fully the grounds on which the whole chemical world, 

 with BerthoUet at their head, went into a great error at a period 

 when investigation was peculiarly alive, and continued in it 

 during the active researches of a quailer of a century. It 

 was this : the weaker acids are unable of themselves to expel 

 the excess of oxygen from the black oxide of manganese, so as 

 to unite with the salifiable oxide; but when aided by any sub- 

 stance, sugar for example, having a strong affinity for oxygen, 

 the salifiable oxide is then developed, which the acid immediately 

 dissolves. This BerthoUet held to be the precise account of the 

 phenomena attending the solution of the black oxide of manga- 

 nese in muriatic acid. The acid has a strong affinity for oxy- 

 gen ; it has also a strong affinity for the salifiable oxide of man- 

 ganese ; hence, a portion of it combines with the excess of 

 oxygen, and flies ofi' in the state of oxygenized muriatic acid : 

 the remainder combines simultaneously with the salifiable oxide 

 thus developed, and forma along with it the common muriate of 

 manganese. 



There are few more interesting explanations of chemical 

 phenomena than those on the one hand urged with so much 

 force by BerthoUet in support of his theory, and those on the 

 other which modern science is now enabled to offer in complete 

 subversion of it. It is entertaining to consider each of these 

 views even separately, and it is highly useful to compare them 

 with each other. We thns find as the result of all the intellect 

 and research which has been brought to bear on the question, 

 that Scheele has the praise of having truly viewed the nature of 

 that important substance, whicli he had also the merit of disco- 

 vering ; while to BerthoUet belongs the scarcely smaller honour 

 of having overturned the doctrine of Scheele, and of having so 

 firmly erected his own hypothesis in its stead, that it remained 

 unshaken and almost unquestioned, until our illustrious country- 

 man Davy succeeded in restoring chlorine once more to its 

 original character. 



(yV) he loiiiiiiiicd.) 



Article II. 

 On lite Chloride of Titamnm. Bv Mr. E. S. George. 



(To the Editors of the Amials of Philosophy.) 

 GENTLEMEN, Grove Terrace, Leeds, Nov. 13, 1824. 



In a paper published in the Philosophical Transactions for 

 1823, Dr. Wollaston states, that the substance from Merthyr 



