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We present a non-LTE analysis of high spatial resolution observations in the radio recombination lines H110$\alpha$, H76$\alpha$, H66$\alpha$, and H42$\alpha$ of the ultracompact H II regions G10.62-0.38 and G29.96-0.02. The regions are of core-halo and cometary morphology, respectively. We find electron temperatures higher than predicted from the Galactic electron temperature gradient observed by Shaver in classical H II regions. We also observe inhomogeneity in electron density. Although collisional broadening depresses line amplitudes at H110$\alpha$, the other lines are closer to LTE. Various models have been suggested for the regions: for G10.62, Keto and Ho have proposed a collapsing core; for G29.96, Van Buren and Mac Low suggest a bow shock. We re-evaluate the models in light of the new data.
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