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A slit micro-rheometer that is used for simultaneous measurement of melt viscosities of four samples has been developed. Sample size is less than 100 mg. The driving force for the rheometer is gas pressure from a nitrogen tank that forces polymer melt into a slit. The melt flow is monitored using a video camera that views the flow front through a sapphire window. The design contains no moving parts and no gaskets or O-rings. Measurements of polyethylene and polycarbonate are presented.