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We report the results of a kinematical Hα survey of the Large Magellanic Cloud (LMC) presented in the form of a kinematical and photometric catalogue of 210 H II regions. The observations have been obtained with a scanning Fabry-Perot interferometer that produced data cubes corresponding to 66 different pointings over this galaxy, each with a field of view of 38 arcmin, covering almost the whole extent of the LMC. We find a bimodal distribution of the Hα luminosity of LMC H II regions. We also derive the local star formation and star formation rate (SFR) per unit area of the nebulae, concluding that star formation in the LMC has proceeded until the present time at an average rate of roughly 0.11 M yr −1 . Also, we do not find any correlation between the SFR or SFR with V (full width at half-maximum for a single Gaussian profile and the difference in velocities for multiple-components velocity profiles), the diameter, the distance to the kinematical centre of the LMC and age of the nebulae. Over most of the LMC V appears to be of the order of 30 km s −1 . However, in a few regions the V of the velocity profiles is as large as 50-100 kms −1 , corresponding to identified supernova remnants and superbubbles undergoing expansion motions.

The detailed radial velocity field of the H II region N105, in the LMC, has been obtained for the Hα and [O III] 5007 lines with a spatial sampling of 9″ and a spectral sampling of 16 and 7kms−1. The peculiar velocity field and morphology indicate that N105 contains four bubble shaped nebulae and two bright distinct quasi-spherical H II regions, more or less coeval, embedded inside another large shell nebula. They are essentially formed by the action of stellar winds of a few exciting stars, born deep inside their parental cloud. This result is deduced from the energy input inside the ionized gas by the stellar winds of early type stars and from dynamical simulations combining the effects of stellar winds with those of high density gradients inside the neutral gas. The size and morphology of the H II region are conditioned by the depth inside the natal cloud; the observed dynamical time-scale of the H II region starts at the moment of blow-out of the molecular cloud.

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