incompressible

They are usually regarded as incompressible; at least, a very great mechanical force is required to compress them.

The physicist could think of but one way: they must assume that the ether is incompressible.

Furthermore, two simple principles are taught by physics: Fluids are incompressible and they seek the lowest hydrostatic level.

This piston is pierced with a small hole, through which the incompressible liquid passes as the piston moves.