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High resolution interferometric observations of the $J$=1--0 rotational transition of CO have been obtained for the outflows from two young embedded protostars, TMC1 and TMC1A\@. The data show that the high-velocity gas has a conical structure with a constant opening angle of $\sim 45^\circ$, with the apex located within 1000 AU of the central star in both cases. We have also imaged both sources in the near infrared at $H$ and $K$ band, and find extended reflection nebulosity coincident with the blueshifted lobes traced by the CO\@. This result suggests the lobes are partially evacuated by the wind or jet driving the outflow, and sets constraints on the mechanism by which the ambient molecular gas is accelerated. Analysis of single-dish CO $J$=2--1 emission from the outflows show them to have dynamical ages of 3--4 $\times 10^3$ years, and mechanical luminosities and momentum fluxes among the lowest yet measured. We compare the observed outflow properties with recent models for the acceleration of ambient gas, and we suggest that the outflows are driven by jets which impart momentum to the surrounding medium through shocks, rather than through the entrainment of molecular material along the edges of the jet.
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