Liquids are commonly known to be incompressible. However, a recently invented class of materials called Porous Liquids, which exhibit permanent porosity in the liquid phase, may be compressible. These porous liquids, when under pressure (0.2-100 MPa), may potentially reduce in volume as the bulk liquid will forcibly occupy the cavities thereby reducing the total volume of the liquid. As the synthesised porous liquids can have up to ten percent free space, there is the potential for these porous liquids to undergo much greater reduction in volume than for conventional liquids when pressure is applied. If successful, these experiments will prove the existence of the first compressible liquid.