on Ihc ne'S! Experiments 9/ M. Deebereiner. 283 



which tlie physical sciences can present. We are acciuainted 

 with the researches wliich lie has made on this subject, only 

 by the announcement which appeared in the Journal des De- 

 buts ot" the 2 tth ot" August last, and whicli is scarcely adapt- 

 ed to give an exact idea oi' it ; anil by a letter iiom M. Kast.- 

 ner to Dr. Liebig, which this gentlema]i, now at Paris, has 

 had the goodness to conniuniica'ie to us. It thence appears that 

 M. Doebereiner has observed that platinum in the spongy state 

 causes, at the ordinary temperature, tiie combination oi hydro- 

 gen with oxygen, and that the develoi>ment of heat resuiting 

 from this action renders the metal incandescent. We has- 

 tened to veriiy a fact so surprising. We have found it very 

 exact ; and as the experiment can be made with the greatest 

 ease, we are about to perform it in the jiresence of the Aca- 

 demy *. 



Having no knowledge of the researches which the author 

 of this beautiful experiment has no doubt undertaken in order 

 to discover its theory, we could not resist the desire of our- 

 selves making some attempts directed towards this object; 

 and although we have not yet attained it, we think that the 

 results of the observations which we have hitherto made, are 

 not unworthy of the attention of the Academy. 



In the experiment wliich we have been making, the spongy 

 platinum becomes incandescent at the time when it is placed 

 at the spot where the hydrogen which issues from the reser- 

 voir is become intimately mixed with the air. From this it 

 was evident, that a small quantity of this platinum being plunged 

 in a mixtnre of two parts of hydrogen and one part of oxygen, 

 there ought to be a detonation ; which the experiment con- 

 firmed. If the proportions of the gaseous mixture deviate 

 much from those of water, or if there be present a gas foreign 

 to the combination, as, tor example, azote, the combination 



that iriUiiini under this form becomes very hot while it produces water; 

 yrdly, that cobalt and nickel in mass cause at about 300° the union cf hy- 

 drogen and oxygen ; 4thly, that platinum in the sponj;y state, when cold, 

 formed water and ammonia with nitrous gas and hydrogen, and also acted 

 on a mixture of hydrogen and protoxide of azote. 



• 'I'he hydrogen gas lamp improved by M. Gay-I,ussac is very convenient 

 for making this ex|)erin)ent. The electrophorus is raised, or tlie conductors 

 merely are detached ; a very slight morsel of i)iatinum in the spongy state 

 is placed at the distance of about two centimetres from the ppeuing by 

 whicli the gas escapes, and as the cock is turned the stream of hydrogen 

 pas falls mixed with air on the surface of the platinum. This becomes forth- 

 with incandescent, and the hydrogen gas, once iuHamed, keeps burning as it 

 flow« out, as if it had been lit by the spark. 



Ill default of a lamp, the common apjjaratus may be cm[)loyed whicli is 

 Used in laboratories i'or obtaining hydrogen gas. h is only necessary to 

 lake care that tin; ua; be let out by a very small opening, in order that it 

 may mix more complelcly with the air. 



N n 2 goes 



