Intelligence a7id Miscellaneous Articles. 14;9 



lain furnace. More lately Gmelin attributed this reduction ^ersc 

 to the presence of gaseous oxide of carbon in the furnace, and 

 assigned the same cause for the reduction of oxide of iron in a 

 porcelain furnace observed by Proust. In fact, it appears con- 

 tradictory that a metal which oxidizes so readily as nickel, by cal- 

 cination in the air, which burns in oxygen gas with disengagement 

 of light, and is even susceptible of spontaneous combustion at com- 

 mon temperatures when it is much divided, should be reduced from 

 its oxide merely by the action of a strong heat. Nevertheless, it 

 does not appear that direct experiments have been made on this 

 subject, although it has often been remarked that during the re- 

 duction of nickel in porcelain furnaces, without the use of charcoal, 

 less metal was always obtained when the crucible was well closed. 

 The following experiments will undoubtedly suffice to justify the 

 opinion, that the reduction of nickel per se is only apparent, and 

 that it is in fact due to the oxide of carbon disengaged m the fur- 



nace. 



Two equal portions of oxide of nickel, equally pure and treated 

 in the same manner, were placed in two crucibles and exposed to-^ 

 gether to the most intense heat of a porcelain furnace. One ot 

 the crucibles was lightly covered, whilst the other was covered m- 

 ternally and externally, with a coating which was vitrifiable by 

 heat ; it was not only covered with a smaller crucible, rendered 

 equally impervious to air, but it was put into another of larger di- 

 mensions, also covered with a second, and well luted. The in- 

 terval was filled with fine sand. When these crucibles were taken 

 out of the furnace after calcination, that is to say, after a fire of 

 eighteen hours, there was found in that which had been lightly 

 covered nearly five grammes of white metallic malleable nickel, 

 incrusted with much fused and unreduced oxide. On the other 

 hand, in the coated crucible, mere fused oxide was found, or con- 

 taining only small globules of metal, of the size of a pin's head ; and 

 their reduction merely proves that it is impossible to render a clay 

 crucible impermeable to gases, in a violent and long-continued heat. 

 —Ann. de Chim. etde Phys. xlviii. p. 257. 



ANALYSIS OF CAMPHOR AND CAMPHORIC ACID. BY M. I.IKBIG. 



Camphor, taking the mean ol two analyses, appeared to consist 



of Hydrogen 9 70'2 



Oxygen 8*5.35 



Carbon 81-763 



100 000 

 According to Bouillon-Lagrange the camphorates of soda, pot- 

 ash and barytes are so little soluble in watet that one part requires 

 from 200 to.SOO parts for solution, whilst according to Hrandes these 

 salts are deli((uesceMt. According to M. Liebig, these differences 

 depend upon the dillerent kinds of camphoric acid on which the 

 experiments were made. 



When camphor is treated with concentrated nitric acid, a yellow 



liquid 



