> with(plots):with(plottools):
> c1:=cylinderplot(1,theta=0..2*Pi,z=-1..1,style=wireframe,color=green):
> s1:=cylinderplot(sqrt(1-z^2),theta=0..2*Pi,z=0.6..0.8,color=blue):
> c2:=cylinderplot(1,theta=0..2*Pi,z=0.6..0.8,color=green):
> s2:=cylinderplot(sqrt(1-z^2),theta=0..2*Pi,z=-1..1,color=blue,style=wireframe):
> display(s2,s1,c1,c2,scaling=constrained);
>