8 ART. 15. — M. OGAWA : PRELIMINARY 



with hydrochloric acid, ammonia gave only a slight turbidity, 

 due apparently to the presence of a small quantity of aluminium. 

 On reduction, however, with zinc and hydrochloric acid, the 

 solution gave an abundant precipitate with ammonia in the 

 presence of an excess of ammonium chloride. The spectrum 

 of the hydroxide thus obtained and dissolved in hydrochloric 

 acid showed the same lines as those observed in the case of 

 thorianite and reinite. The zinc used for reduction was pre- 

 pared by the electrolysis of a pure solution of zinc ammonium 

 sulphate. 



The ammoniacal solution obtained on treating the roasted 

 mineral with ammonia was also found to contain a portion of 

 the element in question originally existing in the mineral ; for, 

 this solution, after acidification with acetic acid and the removal 

 of molybdic acid as barium molybdate, gave no precipitate 

 with ammonia, but, on reduction with zinc and hydrochloric 

 acid, ammonia in the presence of ammonium chloride pro- 

 duced some precipitate from it, which, on examinatiou, was 

 found to be the same hydroxide as that obtained, under like 

 conditions, from the hydrochloric acid solution of the roasted 

 mineral. 



Thorianite, Reinite and Molybdenite. 



It will be seen from what has been stated that the new 

 element is contained in reinite and molybdenite, as well as in 

 thorianite, and, although it can not yet be definitely stated, it 

 is almost certain that molybdenite contains it in even a larger 

 proportion than reinite. 



It may be remembered that Dr. E. H. Büchner, in the 



