Abstract: A level indicating device comprises a compressible container, which is charged with a measuring liquid, and a flexible transparent tube having a first end immersed in the liquid within the container. The second end of the tube may be affixed to a support which has a reference level marking means mounted thereon. When the device is in use, the surfaces of the fluid in the container and in the second end of the tube are exposed to the ambient atmosphere whereby, when in equilibrium, both surfaces will be at the same level.