Tae DE AS St 
EL. W. Hilgard on Luminous Flames. 219 
however, to draw the legitimate conclusion from these facts, at 
® time ; the more as, with the materials I used, it was im- 
Deible to follow the formation of water by progressive oxyda- 
ion, 
The latter difficulty was avoided by Landolt, who, two years 
later took up the same subject, the failure of my health having 
rendered doubtful the prospect of my ever being able to resume 
8oas to carry out the proposed investigation of the other 
Parts of the flame. Zz 
Landolt* used illuminating gas of known composition, and 
Was therefore enabled to determine the deficient factor in my 
analysis, viz., water, So far as comparable his results in general 
Confirmed mine, He felt compelled by the increase of free hy- 
drogen in the higher parts of the flame examined by him, to 
®ssume the occurrence of a reaction between free carbon 
: : (preformed) water ; but he also failed to draw the inevitable 
-Onclusion as to what must happen in the luminous cone. 
* Pogg. Ann., vol. xcix, p. 389, 
