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HISTORY OF SCIENCE. 



enter into the composition of water. Many years ago Mr. Grove (now 

 Sir R. Grove) found that by passing steam through intensely heated 

 tubes the inverse action occurred. The steam was decomposed into 

 its elements, and a mixture of the dissociated hydrogen and oxygen 



could be collected. The quantity was, however, relatively very small 

 compared to the bulk of the steam, and it is evident on consideration 

 that the gases once separated must have become diluted, so to speak, 

 with a large excess of water-gas, or undecomposed steam, in order to 

 escape recombination. A modification of the experiment was after- 

 wards devised which permitted the dissociated gases to be collected 



