2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 85 



of the cell were covered with diaphragms having vertical rectangular 

 openings sufficient to pass a beam that considerably more than covered 

 the first slit of the spectrometer. The absorption cell was sealed with 

 all glass seals in connection on its inlet side with the ozonizers and 

 on its outlet side with an analytical apparatus for ozone. No altera- 

 tions of any sort were made in the regular observing conditions except 

 for the interposition of the cell. Tank oxygen was supplied to the 

 ozonizers under a small constant pressure through the capillary of a 

 glass flowmeter having nujol as the manometric liquid, this flow- 

 meter being calibrated in a series of independent measurements. The 

 exit ozone was analyzed by the method described by Wulf and Tol- 

 man.' The samples, whose volumes were known from the time and 

 rate of gas flow, were collected over potassium iodide solution, set 

 aside, and subsequently analyzed. It is evident that, in the filling of 

 such a cell by sweeping at the low rates of gas flow necessary in such 

 a system for producing ozone of relatively high concentration, a con- 

 siderable amount of time will elapse before the exit gas attains practi- 

 cally the concentration of the entering gas. To study this circumstance 

 a tube was also brought to the analytical apparatus from before the 

 cell as the gas came from the ozonizers allowing a sample of the inlet 

 gas to be taken, and by means of this it was possible to determine the 

 time sufficient for the exit gas to rise nearly to the concentration of 

 the inlet gas. The concentration of the exit gas was taken, in view 

 of the processes of diffusion and mixing going on in the cell, as 

 representative of the ozone concentration in the cell. The ozonizers 

 were of the familiar silent discharge type. For part of the work one 

 alone was used, while for the rest of the work two were used in series 

 and both water-cooled, these giving the largest concentrations em- 

 ployed. Ordinarily over the period of the taking of four ozone holo- 

 grams six analytical samples of the ozone were collected. 



Knowledge gained from earlier work on ozone permits a descrip- 

 tion of the character and position of the absorption." A small fraction 



^ Wulf, Oliver R., and Tolman, Richard C, Journ. Amer. Chem. Soc, vol. 49, 

 p. 1650, 1927. 

 ^ a. Colange, G., Journ. Phys. et le Rad., ser. 6, vol. 8, p. 254, 1927. 



b. Wulf, Oliver R., Proc. Nat. Acad. Sci., vol. 16, p. 507, 1930. 



c. Ladenburg, Erich, and Lehmann, Erich, Ann. Phys., ser. 4, vol. 21, p. 305, 

 1906; Verh. Deutsch. Phys. Ges., vol. 8, p. 125, 1906. 



d. Schoene, E., Journ. Russ. Phys. -Chem. Soc, vol. 16, pt. 9, p. 250, 1884; 

 Journ. Chem. Soc, vol 48, pt. 2, abstracts, p. 713, 1885; Chem. News, vol. 69, 

 p. 289, 1894. 



c. Chappuis, J., Ann. I'Ecole Norm. Sup., ser. 2, vol. 11, p. 137, 1882; Compt. 

 Rend., vol. 91, p. 985, 1880; Compt. Rend., vol. 94, p. 858, 1882. 



