R.P. Langford and D.V. LeMone reviewed drafts of this paper. The American Eagle Brick Company allowed access to its property and is providing security for the trackway sites. P.C. Goodell, S. Lucas, A. Heckert, A. Hunt, and J. Lyons aided Kappus with fieldwork and critical interpretations. Comments from two anonymous reviewers have been helpful in clarifying our concepts.