150 



Product dis- , 

 solved in nitric 

 acid, and mu- 

 riatic added. 



Attempt to 

 fuse it. 



Slightly agglu. 

 tinated merely 



Heated again 



Agglutinated 

 more strongly 



Eagerly ab- 



EXrERlAtENTS ON MOLVBDENA. 



deted chalk; another crucible was put over it; the fire was 

 ■urged to a strong white litat, and in this state it was kept for 

 an hour and a quarter. After the combustion of the oil, the 

 mass was pulverulent, of a deep blue colour approaching to 

 black, and in some parts violet: and after it had undergone 

 the strong heal to which it was exposed, it was entirely of an 

 ash gray, and formed a mass of an earthy appearance, the 

 parts of which had but little cohesion ; the part in contact 

 with the crucible scarcely showed the slightest indication of 

 fusion; and thrown into nitric acid it produced ^ more con- 

 siderable effervescence, than the products of the preceding 

 experiments. The solution thus formed was at first reddish, 

 and afterward became milkwhite. I added concentrated tnii- 

 riatic acid, and boiled to dryness, without any perceptible 

 solution taking place. These circumstances led me to think, 

 that the molybdena was entirely reduced, and that nothing 

 was wariting, but lb unite tlie particles into a button. 



To endeavour to iotin this button, the mass obtained in the 

 preceding experiment, which weighed 3| drachms, was pressed 

 tight into a small crucible, and exposed anew for an hour 

 and half to the most violent forge fire. This heat was so 

 great, that the whole of the surface was vitrified, and the iron 

 melted and burnt in three minutes. After Cooling, the stra- 

 tum bf charcoal powder, with which it had been covered, 

 was scarcely diminished. The molybdena had almost entirely 

 preserved the s&rae form as before; it was of an ash gray co- 

 . lour; its particles were but slightly agglutinated; and no 

 mark of fusion appeared even in the part that adhered to the 

 sides of the crucible. Its vveight was 3f drachms as before. 

 1 took the same mass a third time, powdered it with six 

 grains of charcoal, and exposed it again for an hour and half 

 to a forge fire, which I endeavoured to urge as far as posbi- 

 ble. After cooling, the mass had the same ash gray colour as 

 • before; on turning the crucible Upside down it fell out with- 

 out breaking; and it had a slight degree of consistency, yet 

 iiotwithstanding it was friable between the fingers, and easy 

 to pulverize. No mark of fusion could be discovered in the 

 inside of the Crucible; but the mass had lost six grains of 

 weight, frotn part of it adhering to the sides. The mass be- 

 ing 



