  We have developed a method for deriving the distribution of the Milky Way's
interstellar medium as a function of longitude, latitude, distance and
line-of-sight velocity. This method takes as input maps of reddening as a
function of longitude, latitude, and distance and maps of line emission as a
function of longitude, latitude, and line-of-sight velocity. We have applied
this method to datasets covering much of the Galactic plane. The output of this
method correctly reproduces the line-of-sight velocities of high-mass star
forming regions with known distances from Reid et al. (2014) and qualitatively
agrees with results from the Milky Way kinematics literature. These maps will
be useful for measuring flows of gas around the Milky Way's spiral arms and
into and out of giant molecular clouds.
