Question 50926
I think you just took a step into calculus.
The volume will depend on the area of the base
of the cylinder that is wet.  You know the 
area of the circular base but not of the segment
that is wet.  You would need to figure out the equation
of the circle.  Then, using integration, figure out the
area of the segment of the base that is wet.  The volume
will be the area times the length of the cylinder.
Cheers,
Stan H.