I2 6 On Water and Air. [January 
them. That little narrow cylinder finally breaks when the 
drops are perfedtly formed, and it forms a little drop between 
the two larger drops. We have an apparatus which will 
enable me to show you this. Into the tall glass cell, c 
(Fig. 9), Mr. Cottrell has placed a mixture of alcohol and 
water. At the top of the cell he has placed a funnel, F, with 
its end dipping into the mixture. The funnel, fitted with a 
tap, contains a quantity of oil, and by turning on the tap 
Fig. 9. 
we will allow the oil to issue from the funnel and slowly 
fall through the alcohol and water. There is a drop of oil 
coming from the funnel, and now you will see that it will 
become narrower and narrower, and that little central 
cylinder becoming very fine will break, and you will have a 
little sphere between two larger drops. The appearance of 
these spheres was explained not by Savart but by old blind 
Plateau. This is what Savart noticed in his first experi- 
ments upon liquid veins. I want to show you these drops, 
