Track tagging which is described as two parallel tagging gap or "hot" lines resembling railroad tracks is typically associated with some transportation coils printed on the Cottrell press. Here is an example of one of the Great American issues that appears to have "Track" tagging in the vert. direction. The Thomas Gallaudet was printed on the Cottrell Press. The spacing of a pair of the vert. tagging gaps on the left stamp matches the width of precancel bars exactly. Interesting in that it shows up on only one of the stamps.