1888.] On the Spectrum of the Oxyhydrogen Flame. 347 



Diagram showing the path, described in twenty-four hours by a particle under the 

 influence of the tidal and constant currents of fig. L 



II. " On the Spectrum of the Oxyhydrogen Flame." By 

 G. D. LiVEiNG, M.A., F.R.S., Professor of Chemistry, and 

 J. Dewar, M.A., F.R.S., Jacksonian Professor, University of 

 Cambridge. Received January 18, 1888. 



(Abstract.) 



In a former communication the authors described simultaneously 

 with Dr. Huggins the strongest portion of the spectrum of water, 

 subsequently they described a second less strong but more refrangible 

 section of the same spectrum. M. Deslandres has noticed a third 

 still more refrangible section. The authors now find that the spectrum 

 extends, with diminishing intensity, into the visible region on the one 

 hand, and far into the ultra-violet on the other. These faint parts of 

 the spectrum they have photographed, using the dispersion of a single 

 calcite prism and a lengthened exposure ; and in the present com- 

 munication they give a map of the whole extent observed, and a list of 

 wave-lengfchs of upwards of 780 lines. 



