502 



Occlusion of Hydrogen Gas by Meteoi^ic Iron. 



[May 16, 



IV. ^''On tlie Occlusion of Hydrogen Gas by Meteoric Iron/^ By 

 Thomas Graham, E.E.S. Heceived May 16, 1867. 



Some light may possibly be thrown upon the history of such metals 

 found in nature as are of a soft colloid description, particularly native 

 iron, platinum, and gold, by an investigation of the gases w^hich they 

 hold occluded, such gases being borrowed from the atmosphere in 

 which the metallic mass last found itself in a state of ignition. The 

 meteoric iron of Lenarto appeared to be well adapted for a trial. This 

 well-known iron is free from any stony admixture, and is remarkably 

 pure and malleable. It was found by Wehrle to be of specific gravity 

 7*79, and to consist of — 



*Iron 90-883 



Nickel 8-450 



Cobalt 0-665 



Copper 0-002 



Prom a larger mass a strip of the Lenarto iron 50 millimetres by 13 and 

 10 millimetres, was cut by a clean chisel. It weighed 45-2 grammes, and 

 had the bulk of 5-78 cubic centimetres. The strip was well washed by 

 hot solution of potassa, and then repeatedly by hot distilled water, 

 and dried. Such treatment of iron, it had been previously found, 

 conduces in no way to the evolution of hydrogen gas when the metal 

 is subsequently heated The Lenarto iron was enclosed in a new 

 porcelain tube, and the latter being attached to a Sprengel aspirator, 

 a good vacuum was obtained in the cold. The tube being placed in a 

 trough combustion furnace, was heated to redness by ignited charcoal. 

 Gas came off rather freely, namely — 



In 35 minutes 5-88 cub. centims. 



In 100 minutes 9-52 „ 



In 20 minutes 1'63 „ 



In 2 hours 35 minutes 16-53 „ 



The first portion of gas collected had a slight odour, but much less 

 than that of the natural gases occluded by ordinary malleable iron. 

 The gas burned like hydrogen. It did not contain a trace of carbonic 

 acid, nor any hydrocarbon vapour absorbable by fuming sulphuric acid. 

 The second portion of gas collected, consisting of 9-52 cub. centims., 

 gave by analysis — 



Hydrogen 8-26 cub. centims 85*68 



Carbonic oxide 0*43 „ 4-46 



Nitrogen 0;95 „ 98-6 



9-64 „ 100-00 



The Lenarto iron appears, therefore, to yield 2-85 times its volume 

 of gas, of which 86 per cent, nearly is hydrogen. The proportion of 

 carbonic oxide is so low as 4| per cent. 



