The Unsteady Motion of Viscous Liquids. 
553 
If we take the equation 
a 2 p 
8 p fi l 
( 
1 — e TtCL* 
). 
(5) 
and let l equal L , where L is the whole length of the tube, and 
let V be the distance the bubble has moved from the end of the 
tube, we shall obtain 
(9) 
in which C can readily be determined, depending as it does on 
the position of the bubble at the beginning of the flow. The 
different values of t can be compared with those found from 
experiment, constituting a second method for determining the 
retarding influence of the meniscus. 
A knowledge of the retarding influence of the meniscus would 
have important applications to problems in the seepage of 
water through soils or other porous media. 
West Superior , Wis ., December , 1898. 
