Champagnat

Claim 1

A SCREEN FOR REDUCING LOSSES BY EVAPORATION OF LIQUID, CONTAINED IN A CLOSED TOP STORAGE VESSEL OF WHICH THE WALL OR WALLS ARE UPRIGHT, SAID SCREEN COMPRING A METAL FRAMEWORK, SAID FRAMEWORK COMPRISING A PERIPHERAL FRAME, A PLURALITY OF SPACED PARALLEL COPLANAR BEAMS ATTACHED AT THE END PORTIONS THEREOF TO SAID PERIPHERAL FRAME, SAID PERIPHERAL FRAME AND EACH OF SAID BEAMS COMPRISING A VERTICAL WEB, SAID SCREEN ALSO COMPRISING A SHEET OF MATERIAL IMPERVIOUS TO VAPORS OF THE LIQUID STORED, SAID IMPERVIOUS SHEET COMPLETELY COVERING SAID FRAME AND SAID BEAMS AND BEING ATTACHED THERETO AT SPACED POINTS THROUGHOUT SAID FRAME AND BEAMS, FLOATS, SAID FLOATS BEING ATTACHED TO SAID FRAME AND BEAMS AT THE BOTTOM EDGE THEREOF AT SPACED POINTS THROUGHOUT SAID FRAMEWORK, SAID FLOATS BEING POSITIONED TO CAUSE THE SCREEN, WHEN IN USE, TO FLOAT WITH SAID SHEET ABOVE THE LEVEL OF THE LIQUID AND WITH THE LOWER EDGES OF THE VERTICAL WEBS OF THE FRAME AND BEAMS AND A PORTION OF THE FLOATS IMMERSED IN THE LIQUID WHEREBY VAPOR OVER THE LIQUID IS TRAPPED BELOW THE IMPERVIOUS SHEET IN POCKETS FORMED BETWEEN THE PERIPHERAL FRAME AND SAID BEAMS.