Concave menisci and water tension?

Question

Why (and how) do concave menisci induce negative pressures on water?

Answer 1

The forces acting between molecules of the same kind are called 'Cohesive' forces.

There is also an attraction between different molecules called 'Adhesive' forces.

Adhesion can be greater than Cohesion.  For example:  If a small glass vessel is filled with water, the surface of the water is not completely flat but curves downwards into a concave shape inducing a 'Negative Pressure' effect.

This is due to the Adhesion between the water and the glass molecules being greater than the Cohesion of the water.  

Opposite to this, if another glass is filled with mercury, the curve becomes convex due to the mercury's Cohesion being greater than the Adhesion between the glass and the mercury.

This curvature of the surfaces is known as the 'MENISCUS'.