  This papers searches for evidence of mass concentrations along the path of
radio pulses in the PPTA2 survey data release. Radio pulse travel times are
influenced via gravitational fields along the path from the source to the
observer. Transient time delays in transit are a useful measure of the matter
distribution along the path. Many pulsars have very well understood timing
solutions with predicable arrival times and can be used to sample the mass
variation. Changes in the source, observer and mass concentration positions
produce changes in arrival times which can be significant for precision pulsar
times. Twelve candidates are reported from this search.
