DISOXIDATION OP IRON BY HIpROGEN GAS. 3^ 



xvhat I have deduced from the experiments of several able 

 chemists on the composition and decomposition of oxidules 

 of iron. It is also the same as Mr. Desroches has deduced 

 from the experiments he made this year at Moutiers. 



It follows too from these experiments, that the oligist 

 iron is more oxided than the oxidule, as the learned Mr. 

 Haiiy had concluded from the colour of these two ores 

 when powdered. 



But when we have taken account of the carbon and Loss in the re- 

 oxigen combined in the metallic button obtained from the^^JJJLJJJ"j^J^^jJ^ 

 disoxidation of oxides of iron by charcoal, it appears, that accounted ioi. 

 the loss they undergo in their reduction is still less than that 

 which occurs when they are disoxided by hidrogen ; since in 

 the latter case the oxidule of Cogne lost 46 to 100 of iron, 

 while it lost but 32 in the reduction by charcoal; and the 

 iron of Elba lost 54 with hidrogen, and only 36 with char- 

 coal. 



Is this difference ascribable to the solvent action of hi- Iron apparently 

 drogen ? Some observations seem to warrant this conclusion. cardeToff by 

 1, When the hidrogen gas obtained by the decomposition of the hidrogen, 

 water passed over iron, or by dissolving this metal in acids, 

 or otherwise, is preserved in jars over water, the interioF 

 of the jars sometimes becomes coated with a slight stratum 

 of oxide of iron. 2, At the end of the account of his ex- 

 periments Mr. Desroches had added the following note. 

 *' A great deal of ferruginous hidrogen gas was evolved, as 

 I found by its smell ; so that probably some iron was lost 

 in the passage of the hidrogen gas through it." 



I do not think however, as Mr. Desroches observes, that This deserves 

 we should hastily conclude hidrogen to have a solvent ac- "^^^'"^y* 

 tion on iron from his experiments alone. They should be 

 repeated and varied in several waysy before we decide on 

 a fact of such importance. It is sufficient for me at pre- 

 sent to have called the attention of chemists to a result, ihat 

 is worthy their consideration. 



X. Determination 



