INTER.VAL COHESION OF LIQUIDS. 13 



(as shown in fig. 3) , but only for a few seconds. Wlien 

 the mercury fell, if the column broke anywhere near the 

 top of the tube, it gave way with a loud click. But this 

 was by no means always the case. The mercury would 

 sometimes separate nearly 30 inches down the tube ; and 



Fig. 4. 



r7=] 



501N 



then the appearance of the upper portion falling was very 

 singular : the upper portion of the column remained 

 intact ; and a stream of mercury fell from its under surface, 

 as shown in fig. 4, breaking up into globules as it came 

 into contact Avith the lower portion, with a loud rattling 

 noise. I was unable to get the column in the tube thus filled 



