200 M. Peschier's Method of extracting 



aside the feeling of respect. His name is coupled in my mind 

 with that of Laplace when I think of capillar}' attraction. He 

 has many other honours, and I am happy to know that he will 

 soon have more. Professor Leslie is too far above an anony- 

 mous writer to be affected either by his praise or blame, but 

 for that very reason I deem his errors dangerous. Now-a-days 

 every great mind is bent on extending the boundaries of sci- 

 ence. The questions and disputes of philosophy that sur- 

 round its entrance are disregarded; and error, when recom- 

 mended by authority, is apt to be received by the multitude 

 without due examination. In such a state of things the con- 

 tributions of a humble individual may not be unacceptable. 

 March 19, 1825. 2. 



XXXIIL Method of extracting Titaimim from Minei'ah, and 

 of separating it completely from the Substances with which it 

 is found combined. By M. Peschier. 



VyHEN I made known in 1821 and 1822 the results of 

 '* my analytical researches on the micas [Journal de 

 Physique), and communicated in the following year to M. Vau- 

 quelin those which I had obtained from the talcs, I could not 

 suppose that the process which I had followed was not exact, 

 and that the proportions of titanium which I had stated were 

 exaggerated; for the pro)ierties analogous to those of silica, 

 alumina, magnesia, and lime, which this principle possesses, 

 were not known to me: these earths also have sometimes 

 been looked upon as pure when it was found united with 

 them, and at other times that which was believed to be pure 

 titanium was a mixture of titanium and of one or the other of 

 these earths. 



But liaving since discoA'ered these different properties arid" 

 the means of separating these principles with exactness, I oc- ~ 

 cupied myself in rectifying several of my analyses. L commu- 

 nicated some of them this spring to our Society of Natural 

 Philosophy and Natural History, and should not have made 

 them known prior to the publication of the work on titanium 

 with which Lam occupied, if the note of M. Vauquelin on the 

 presence of titanium in micas, inserted in the September Num- 

 ber of the Annates de Chimie et de Physique, p. 67, had not 

 obliged me to anticipate this period ; for, in discovering tita- 

 nium in all the micas, this pliilosopher informs us that those 

 •which contain the greatest quantity of it did not yield him a ' 

 hundredth part. 



I shall first describe the order of the processes to be fol- 

 * From Ai'malei de Chimie, vol. xxvii. p. iiSl. 



lowed 



