Abstract: A device for sucking up solid objects, such as manganese modules, from the sea bed having a suction tube within which the density of the water is reduced by feeding in to said tube form-retaining light objects by means of a vertical supply conduit filled with air under high pressure through which the light objects fall down to enter the suction tube through a water slot, the said supply conduit being connected at its lower and upper end to an air filled return conduit to form a closed circuit, mechanism being provided to generate a downward flow of air in said supply conduit.