237 



As these experiments will show, the results during the 

 latter part of the series were very irregiilar. By moving 

 the tiibe up and down the meniscus was nearly immoveable, 

 from which it follows that the tube was now made unclean 

 by some substance. Nothwithstanding repeated washing with 

 distilled water, this tube could not be made abie to show 

 results. What this unknown substance may be, has not 

 been discovered. 



As a new tube n:o I was taken, the dröp was seen 

 in a distance of: 



13,3 cm instantly and in 24,9 cm after some seconds. 



After some vain experiments with a positive point, we 

 received with the negative at a distance of 24,9 cm a dröp 

 after 2'^27% ^127^ and 3"iO^ 



Because the tubes, hitherto used, did not give constant 

 results, new tubes of the same dimensions were made with 

 a lacing in at its upper end. Their length was 11, o cm. 

 With these tubos experiments were made to answer the 

 questions: 



^) The dröp was formed at a distance of 2,3 cm above meniscus. 

 -) D:o d:o at a distance of 1,9 cm above meniscus. 



