[ 414 ] 

 XLIX. Intelligence and Miscellaneous Articles, 



ARTIFICIALLY CRYSTALLIZED OXIDE OF ZINC FROM A BLAST- 

 FURNACE. BY RICHARD COWPER, ASSOCIATE OF THE ROYAL 

 SCHOOL OF MINES. 



ON the occasion of the removal of the lining of one of the blast- 

 furnaces at the Tredegar Iron Works, a crystalline substance 

 was observed coating the bricks of the hearth and boshes, by Mr. 

 James Colquhoun, the manager of the works. On examining the 

 bricks, I obtained some bright and transparent but rather small 

 crystals in sufficient quantity for examination. They proved to be 

 practically pure oxide of zinc, which, I am informed by Dr. Percy, 

 is well known as a crystallized blast-furnace product. 



An analysis gave 100*13 per cent. ZnO, with a trace of Al 2 3 

 and Fe 2 3 , possibly due to adherent particles of the brick which 

 formed the " gangue." 



The crystals are yellow and greenish yellow in colour transpa- 

 rent to translucent, and belong to the hexagonal system, the fol- 

 lowing forms being noticed : — 



(1) oo P. OP. (2) oo P. P. 



|(3) ooP.OP.P. (4) ooP.ooP2.0P.P. 



The native oxide of zinc, zincite or spartalite, also belongs to 

 the hexagonal system • but crystals of this mineral appear to be 

 rare. 



Tredegar Iron Works. 



ON THE CHEMICAL AND SPECTROSCOPIC CHARACTERS OF A NEW 

 METAL (GALLIUM). BY LECOQ DE EOISBAUDRAN. 



The day before yesterday (August 27, 1875) I found some indi- 

 cations of the probable existence of a new element, in the products 

 of the chemical examination of a blende from the Pierrefitte Mine, 

 Valley of Argeles, Pyrenees. 



I have at present ascertained as follows : — 



(1) The oxide (or, perhaps, a subsalt) is precipitated after some 

 time by metallic zinc in a solution containiug chlorides and sul- 

 phates. It does not appear to be the metal itself reduced by the 

 zinc. 



(2) The chloride is precipitated by a small quantity of ammonia. 

 In a mixture containing excess of chloride of zinc the new substance 

 is precipitated before the zinc when the liquid is treated with an in- 

 sufficient quantity of ammonia to throw down the latter. After 

 the second precipitate the proportion becomes minute, almost the 

 whole being found in the first fraction. 



(3) Even in conditions which must correspond to a state of per- 

 oxidation*, the oxide is soluble in excess of ammonia. 



* On the hypothesis that the substance has two oxides, analogous to 

 those of iron. 



