Construction and engineering department of Pennsylvania Traction Company. Left to right: William harkins, masonry inspector; Harry McGinnis, chainman; H. D. hatzfeld, levelman; W. O. Groff, transitman; William Henderson, principal assistant engineer; S. R. Slaymaker, chief engineer; Frank T. Weiler, Assistant engineer; John Dickey, transitman; John Eby, graughtsman; Frederick Unger, rodman; Milton Hartman, tie inspector; John Huffnagle, axeman; William Rathfon, ballast inspector.