1865.] Chemistry. 665 



zirconia is but a weak acid. It expels carbonic acid from carbonate 

 of soda at a bigb temperature, and forms the compound Na 0, Zr O s , 

 wbicb is deconrposed by water, zirconia being separated. At a higher 

 temperature the compound 2 Na 0, Zr 2 is produced, and when this is 

 treated with water a crystallized hydrate of zirconia separates. It is 

 remarkable that when zircon, a native silicate of zirconia, or a cor- 

 responding mixture of silica and zirconia, is heated with carbonate of 

 soda, only the zirconia enters into combination with the alkali. 



Some compounds of Thorium, another rare metal, have been experi- 

 mented upon by Delafontaine, Chydenius, and others, principally 

 with the view of determining the atomic weight of the metal, which 

 had been left uncertain by Berzelius.* Although not quite in accord- 

 ance with one another, they agree in assigning a lower equivalent 

 weight than that of Berzelius. This last authority gave 844 ■ 9 as the 

 equivalent of thorina ; but, according to Delafontaine and Chydenius, 

 the number should be 823 (O = 100). Chydenius considers thorina 

 as the analogue of zirconia and titanic acid, and has assigned to it the 

 formula Th 2 ; Hiortdahl, however, states, in one of the papers quoted 

 above, that thorina will, under no circumstances, combine with bases. 



The compounds of Niobium have been of late the subject of many 

 researches by Deville, Marignac, and .Blomstrand. The last-named 

 author states,! as ^ n e resu lts of his experiments, that only two metals 

 constitute the niobium group — niobium and tantalum. Bose's pelo- 

 pium has already been proved to be niobium, and Von Kobell's 

 dianic acid, Blomstrand states, is niobic acid, pure, or perhaps mixed 

 with a little tantalic acid. With regard to the atomic weight of 

 niobium, which Bose was unable to fix with certainty, the writers 

 named above differ widely. Deville J gives the number 47 or 48 ' 3 ; 

 but Blomstrand, while admitting that his experimental results are not 

 concordant, states his belief that the true equivalent of niobium is 39. § 



We read that a Swedish chemist has succeeded in discovering a 

 cheap and easy method of reducing and casting tungsten. From what 

 is known of the properties of this metal, it would hardly seem suscep- 

 tible of useful application by itself ; but, in the form of alloys, as in 

 the case of tungsten-steel, it may be of great value. 



An easily fusible alloy may have an interest and use to many of 

 our readers, so we give the composition of the most easily fusible we 

 have met with in our reading. Von Hauer|| states that an alloy, 

 having the formula Cd 4 , Sn 5 , Pb 5 , Bi 5 , is perfectly fluid at 65 • 5 C. The 

 proportions for making this compound can be easily calculated from 

 the equivalent weights of the metals. 



Not many of our readers, probably, have seen pure iron, and they 

 may perhaps be astonished to learn, upon the authority of Stahl- 

 schmidt,^[ that the metal which the author obtained by reducing the 



* ' Bulletin de la Societe Chimique de Paris,' April, 1865, p. 278. 



f ' Comptes Rendus,' t. lxi. p. 337. 



X ' Comptes Rendus,' June 12, 1865. 



§ ' Annalen der Chem. und Pharm.,' Bd. lix. s. 198. 



|| ' Journal fur prakt. Chem.,' Bd. 96, s. 436. 



Tf ' Poggendorffs Annalen der Chem. und Physik,' No. 5, 1865. 



