tension is uniform throughout the various cables the cables are alternatively extended or retracted as a function of pressure differentials in a manner well known in the art so as to provide an even stress distribution throughout however a few of these ribs 14 may be of rigid configuration so that the distance between the collar and the ship can be kept constant this rigidity may come from the use of a rigid foam material or air pressure as shown by the structure of fig8 in this event the units designated by reference numeral 19 would be air compressors or compressed air storage tanks these sources of air 19 in any event also are operatively connected to the collars so as to assure that they are maintained in an inflated condition when the oil containment device is not to be utilized deflating the collars and ribs and storage of the sheets provide a storage structure which is relatively unobtrusive and compact in form fig9 and 10 and 15 through 18 depict a compartmentalization technique associated with a vessel wherein discrete quantums of fluid substances such as oil can be stored to minimize severity of any spill should it occur through a puncture in the outer plating of the vessel in addition however it should be appreciated that different types of liquids could be stored in different compartments thereby providing versitility to the loads that are able to be carried therewithin the vessel or ship s as shown in cross section fig1 is provided with a plurality of these compartments all of which can be characterized in that indicators are integral with these compartments 20 to indicate the liquid level status of each compartment specifically these compartments 20 generally regarded as.