Blowpipe oxyhydrogen

W. N. Hartley 57 found the alkali chlorides in the oxyhydrogen blowpipe flame give lines of elements with a more or less continuous spectrum believed to be due to the respective metals. Lithium chloride, however, gives no continuous spectrum. G. P. Thomson studied the anode rays from lithium chloride and other alkali halides. 

Footnote 8 Page 58. Bunsen has calculated that the temperature of the oxyhydrogen blowpipe is 8061° Centigrade. Hydrogen burning in air has a temperature of 3259° C., and coal-gas in air, 2350° C.]... 

The chemical properties of chromic oxide.—E. D. Clarke said that chromic oxide is not decomposed by the oxyhydrogen blowpipe flame and J. J. Berzelius found that it is not decomposed by hydrogen at a red-heat. For the electroxidation of chromic oxide, vide chromic acid, etc. According to R. Saxon traces of chromic acid are formed by the anodic oxidation of chromic oxide in pure water the addition of manganese dioxide to the chromic oxide increases slightly the yield of chromic acid. Much more rapid oxidation ensues in the presence of calcium or potassium hydroxide or both. In soln. of alkali chlorides containing a little chrome-alum, chromic oxide is rapidly oxidized at the anode to chromic acid. 

Daniell published an introductory lecture and a syllabus of his course. His hygrometer is based on Dalton s dew-point method (see Vol. Ill, p. 763). Daniell s pyrometer depended on the expansion of a metd bar. He introduced the modern form of the oxyhydrogen blowpipe. The Daniell cell is considered later (see p. 685). 

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