XOTE ON A NEW ELE3IENT ALLIED TO -MOLYBDENUM. 7 



crop after adding alcoliol to the mother liquor and allowing it 

 to stand for two days. From these two fractions, which looked 

 exactly alike, water of crystallisation, ammonium oxide and the 

 residual oxide or oxides were determined with practically the 

 same results. 



The attempt, which was next made, to prepare the sodium 

 salt resulted in showing the compound nature of the ammonium 

 salt. The oxide, obtained from the ammonium salt, was fused 

 with an equivalent quantity of sodium carbonate, calculated from 

 the equivalent weight already determined on the supposition that 

 the sodium salt would have the composition x^a2X04 ; the fused 

 mass was dissolved in Avater and the solution evaporated, when 

 hygroscopic crystals were obtained. Under a microscope, these 

 were found to consist partly of thin plates and partly of small 

 needles, but, owing to their hygroscopic nature, their mechanical 

 separation was found to be impossible. 



Isolation of the element was, at last, effected through the 

 electrolysis of the ammonium salt. On electrolysing an aqueous 

 solution of the ammonium salt at a tem^^erature of 60°-70'^, 

 using a current density of 1 ampere per 100 sq. cm. and a 

 potential difterence of 4 volts, a black substance deposited on 

 the cathode. It was found to contain molybdenum, doubtless, as 

 a hydrated sesquioxide, and, on heating it with 2N-hydrocliloric 

 acid, the molybdenum compound gradually dissolved away to 

 form a dark brown solution. Treatment with hydrochloric acid 

 was repeated, until the fresh acid was no longer coloured brown. 

 A portion of the residue (hydrated lower oxide of the new 

 element?), which Avas graphitic in appearance, was boiled with 

 nitric acid, the whole evaporated to dryness and extracted with 

 ammonia. The ammoniacal solution was also evaporated to dryness 



