PARAMETER (NROW =1024)      ! maximum number of particles in 1D
      PARAMETER (NGRID =128)      ! zero-level mesh in 1D
                                  ! must be equal to ng in ART
      PARAMETER (Nmaxpart = 512**3+2e6)  ! max number of particles for this run
                                  ! Nmaxpart must be less than NROW**3
      PARAMETER (LevelParticles =2) ! Level at which particles are expected to run
                                    ! at the first time-step
                                    ! This defines offset of initial velocity:
                                    !     da/2/2**LevelParticles
                                    ! Offset of coordinates = 0.5/2**LevelParticles
      PARAMETER (nbyteword = 4)   ! defines length of direct-access:1or4
      PARAMETER (Lblock=4)