182 Action of Platinum on Combuslible Gases. 
cause them to detonate. In mixtures which were non-explo- 
sive, oars : redundancy of one or other gas, the combina- 
tion of their bases went on silently, and the same chemical 
compounds were formed as by their rapid cotituainent 
In 1823, Professor DoBEREINER, of Jena, ascertained 
“that when platinum, in the form of sponge, is introduced 
into an explosive mixture of oxigen and pg ae the me- 
tal, even though its temperature had not been previously 
raised, immediately glows, and causes the union of the two 
gases to take place, sometimes silently, at others with detona- 
tion. It is remarkable, however, that platinum, in this form, 
though so active on mixtures of oxigen and hydrogen, pro- 
duces no effect, at common temperatures, on mixtures of oxi- 
gen with those compound gases, which were found by Sir 
Hompbre y Davy to he so readily acted upon by the heated 
wire.” Dulong and Thenard found that at the common 
temperature of the atmosphere, carbonic acid slowly unites 
-_ oxigen = the agency of — spent oe it does 
esting phenomena in gaseous analysis mer thus be solved ; 
for — it might be expected that platinum sponge would 
separate hydrogen from carburetted hydrogen, leaving the 
latter dnaered: 
Thi 
* The proportions used by Dr. He ere 2 Fade ene chi 
na clay and 
3 of spo ets atinum, mixed with ory, wore ich was snoulded 
spong 
into small ut the size of 
pens “the ono best adapted to 
See of acti c= - obtained by using “i oo lig 
ee muriate, after puttin vit ks the crucible. too light 
and poroits,the sponge ie ans co shicth! ninitee nf re: 
ae nth apd te ot amated. wou hid this balls oc oaaee 
oe ==) ed after their full action. they: see e fastened to pieces of pla- 
