44 Mr. E. M. Wellisch on the Motion of 



reduced to atmospheric pressure on the assumption of the 

 validity of the law pk = const. 



Freq. 



/. 



V 

 mm. 



v.. 



h. 



K. 



Remarks. 



807-9 



•545 



35-5 



1-4 



4232 



197-6 



Fresb. 



8206 



•518 



54 



2-45 



2587 



183-8 





824-5 



•527 



87 



2-8 



2233 



255-6 





796-8 



•530 



137 



4-5 



1336 



241-0 





833-3 



•540 



79 



3-0 



2056 



214-0 





830-1 



•545 



54 



8 



761-7 



54-1 



2 davs old. 



834-2 



•550 



23 



2*2 



2757 



83-4 



do. 



833-3 



•540 



79 



4-6 



1341 



139-4 



2£ hrs. old. 



828-2 



•540 



81 



7-35 



834 





f 79 mm. C0 2 

 I +2 mm. air. 



In fig. 5 there is given an E curve for freshly prepared 

 hydrogen at atmospheric pressure; the value of K deduced 

 from this curve was 1700 cm. per sec. 



Fig. 5. 



The values of K for freshly prepared 00 3 are scarcely in 

 sufficient agreement to justify the assignment of an average 

 value. It is evident from the table that the electron velocities 

 are very sensitive to the presence of impurities ; the highest 

 value of K obtained was 255 cm. per sec. ; but even this 



