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Claim 1

A FILTER FOR SEPARATING SOLIDS IN A FLUID PETROLEUM SOLUTION CONTAINING SOLIDS COMPRISING A VESSEL HAVING AT LEAST ONE SIDE AND A BOTTOM, SAID BOTTOM FORMING A HOPPER ADAPTED TO HOLD SEPARATED FLUID PETROLEUM, A CAGE SLIDABLY MOUNTED IN SAID VESSEL, A SUPPORT UPON WHICH SAID CAGE IS MOVABLE OUTSIDE OF SAID VESSEL, SAID CAGE FORMED OF A TOP, A BOTTOM AND AS MANY SIDES AS THE VESSEL, SAID CAGE HAVING AT LEAST ITS TOP AND BOTTOM COVERED WITH METAL FILTER CLOTH, SAID CAGE ADAPTED TO BE FLUID TIGHT EXCEPT WHERE COVERED BY SAID FILTER CLOTH, SAID CAGE WHEN COVERED WITH SAID FILTER CLOTH BEING THE ONLY FILTER IN SAID VESSEL, SAID FILTER CLOTH ADAPTED TO SEPARATE THE COARSER SOLIDS FROM FLUID PETROLEUM CONTAINING SOLIDS WHEN SAID PETROLEUM IS PASSED THROUGH SAID FILTER CLOTH, RELEASABLE MEANS FOR SUPPLYING SAID FLUID PETROLEUM SOLUTION TO SAID CAGE THROUGH THE TOP THEREOF, WHEREBY THE FLUID PETROLEUM IS SEPARATED FROM SAID SOLID MATTER AND PASSES INTO SAID HOPPER WHILE SAID SOLID MATTER IS COLLECTED INSIDE SAID CAGE, SAID CAGE HAVING ITS BOTTOM HINGED TO OPEN DOWNWARDLY TO DISCHARGE SAID SOLID MATTER COLLECTED THEREIN, AND MEANS FOR DELIVERING THE SEPARATED FLUID PROTECTION FROM SAID HOPPER.