  In an attempt to understand the dynamics of collapsing starless cores, we
have onducted a detailed investigation of the velocity fields of two collapsing
cores, L694-2 and L1197, with high spatial resolution HCN J=1-0 maps and Monte
Carlo radiative transfer alculation.
  It is found that infall motion is most active in the middle and outer layers
outside the central density-flat region, while both the central and outermost
parts of the cores are static or exhibit slower motion. Their peak velocities
are 0.28 km s^{-1} for L694-2 and 0.20 km s^{-1$ for L1197, which could not be
found in simple models. These velocity fields are roughly consistent with the
gravitational collapse models of the isothermal core; However, the velocity
gradients inside the peak velocity position are steeper than those of the
models.
  Our results also show that the density distributions are ~ r^{-2.5} and ~
r^{-1.5} in the outer part for L694-2 and L1197, respectively. HCN abundance
relative to H_2 is spatially almost constant in L694-2 with a value of 7.0 X
10^{-9}, while for L1197, it shows a slight inward increase from 1.7 X 10^{-9}
to 3.5 X 10^{-9}.
