526 EXPERIMENT STATION RECORD. 



"There is a close analogy between ozone and ammonia with regard to their 

 synthesis and decomposition; both are formed by sparking, and both are completely 

 decomposed by heat." 



The author criticizes the attempt of Haber and van < >ordt, noted above, to fix the 

 dissociation constant of ammonia at different temperatures as based upon entirely 

 insufficient data. 



On the formation of ammonia from the elements, F. Habek and G. van Ookdt 

 (Ztschr. Anorgan. Chan., 47 {1905), No. 1, pp. 4%-44). — This is a defense of the 

 authors' investigations on this subject against the criticism of Perman, noted above. 

 It is also pointed out that Perman' s article is not clear'as to the part played by vapor 

 of water in the synthesis of ammonia by heat. 



The action of nitrogen on water vapor at high temperatures, O. F. Tower 

 {Jour. Amer. Chem. Soc, 27 {1905), Xo. 10, pp. 1209-1216).— Studies are reported of the 

 rate and extent to which nitrogen combines with the oxygen of water vapor at high 

 temperatures. The amounts of nitric acid which were formed in the experiments 

 reported were very small, and it is shown that theoretically only 0.33 per cent of a 

 gaseous mixture of 3 parts nitrogen and 1 part water vapor can be expected to be 

 converted into nitric oxid at a temperature of 2,000° C. and 1.5 per cent at a tem- 

 perature of 3,000° C. 



The action of nitrogen on water vapor, O, F. Tower {Ber. Deut. Chem. Gesell., 

 38 {1905), Xo. 12, pp. 2945-2952). — Noted above from another source. 



Nitric acid from air, H. R. Carveth and C. L. Rand {Sibley Jour. Engin., 1905, 

 May; abs. in Engin. and Min. Jour., 80 {1905), No. 11, p. 485).— The authors review 

 the various processes which have been devised for the production of nitric acid by 

 electrical discharges througn air, and give a table showing the approximate yields 

 obtained by various experimenters as follows: 



Nitric acid produced by different <lt<-iri<-<il methods. 



Date. 



Experimenter. 



Nitric 

 acid 

 pel- 

 kilo- 

 watt 



hour. 



Gra7ns. 



1897. . Ravleigh 49. 1 



1900. J McDougal and Howies (best vield) 33.8 



1902. . Kowalski 55. 



1903. . Muthmann and Hofer 70. 



1897. . I Crookes 74. 



1902. . Bradlev and Lovejoy 83. 



1904. . Birkeland and Evde 110. 



It is thought that these results "indicate that commercial success may yet be 

 attained. The main improvements which may possibly have an advantageous influ- 

 ence on the yield of nitric acid by the electric flame are: («) A vessel so designed as 

 to produce the best hot-cold effect; {h) spark long drawn out; (c) low current and 

 rapid alternations; {d) increased pressure; (e) rapid passage of gases and the intro- 

 duction of the gases in the correct proportions; (/) temperature below 1,200° C." 



It is considered probable, however, that indirect methods, such as the nitrid or 

 cyanid process, may be found to be more economical. 



On the oxidation of the nitrogen of the air by means of electrical dis- 

 charges, F. vox Lepel {Ber. Dent. ('hem. Gesell., 38 {1905), No. 11, pp. 2524-2533, 

 figs. 2). — This is a continuation of previous investigations (E. S. R,, 15, p. 847) in 

 which the author describes apparatus and results obtained in experiments in which 

 the rate of oxidation was observed in case of electrodes rotating in opposite direc- 

 tions. The effect of previous warming of the air and of altering the form of the 

 apparatus was also studied. 



