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High spatial resolution observations are presented of the compact outÑows associated with the young protostars TMC-1 (IRAS 04381]2540) and TMC-1A (IRAS 04365]2535) in Taurus. Emission in CO(1È0) imaged with the Owens Valley Millimeter Array shows the outÑow lobes to be conical close to the star. Analysis of the outÑow dynamics indicates that these objects are low-luminosity versions of the energetic outÑows more commonly observed. Near-infrared images at H and K bands show a close correspondence between reÑection nebulosity and the location of high-velocity gas and suggest the outÑow cavity is evacuated, as do position-velocity diagrams of the CO(2È1). Comparison of the J \ 1È0 transition with emission in the 2È1 line indicates that the excitation temperature in the high-velocity gas is higher than the surrounding Taurus cloud. We place limits on the inclination of both objects by comparing the data with theoretical outÑow models and conclude that i D 40¡È70¡ for both objects. The deprojected opening angles of the outÑow cones are then in the range 30¡È40¡.None of the current outÑow models satisfactorily explains the results for TMC-1 and TMC-1A, which are among the youngest class I sources in Taurus. We Ðnd their outÑow structure shares many similarities with the more obscured and possibly younger class 0 objects, B335 and L1448-C. The main difference is the lower mechanical luminosities of the TMC-1 and TMC-1A outÑows, reÑecting a factor of 3È4 smaller linear extent and velocity and a factor of 10È20 lower mass than the L1448-C molecular jet source. Taken together, the four protostars share the common properties of (1) conical outÑow lobes close to the star, (2) evacuated outÑow cavities, and (3) relatively wide 30¡È45¡ opening angles. A successful theory of young stellar outÑows must be able to explain these characteristics.

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