48 



Prof. E. Wiedemann on the 



Dark space 14 millim. Limit of positive light at 120 

 (curve d). 



E. 



A. 



E. 



A. 



E. 



A. 







26 



40 



12 



150 



1 



14 



22 



62 



8 



260 







22 



20 



100 



2 







Dark space 8 millim. Positive light begins at about 75 

 (curve e). 



E. 



A. 



E. 



A. 



E. 



A. 







17 



52 



2 



Ill 



1 



8 



11 



75 



1 



125 







26 



6 











II. Narrower tube 18 millim. wide (fig. 6). 



Dark space 14 millim. Green phosphorescent light appeared 

 even at the edge of the dark space, which, however, cannot be 

 produced by the kathode-rays, since these issue from only a 

 small portion of the kathode, and form a very slightly 

 divergent pencil of rays, which at a distance of 14 millim. 

 certainly does not meet the walls of the tube. 



The boundary between positive and negative light cannot 

 be determined. Also there are no stratifications. Fig. 6/ 

 gives again the results obtained. The horizontal dimensions 

 are in this diagram twice as great, and the vertical dimensions 

 half as great as in the former ones. 



E. 



A. 



E. 



A. 



E. 



A. 







38 



44 



95 



130 



11 



8 



47 



65 



66 



170 



3 



14 



71 



100 



25 



222 







30 



100 



1 









Dark space about 10 millim. (curve g). 



E. 



A. 



E. 



A. 



E. 



A. 







51 



40 



112 



130 



11 



10 



71 



60 



86 



180 



2 



16 



92 



100 



32 



220 







22 



102 











