"The Erie's general superintendent (Daniel McCallum) stressed the value of adhering to explicit lines of authority and communication. "All subordinates should be accountable to and be directed by their immediate superiors only; as obedience cannot be enforced where the foreman in immediate charge is interfered with by a superior officer giving orders directly to his subordinates." McCallum, nevertheless, failed to define precisely the relationship between the geographical division superintendent and the other functional managers of the division who reported to the general superintendent. He saw the problem clearly enough, pointing out that there were "some exceptions" to the rule that subordinates can communicate only through their senior officers. For example, "Conductors and station agents report, daily, their operations directly to the General Superintendent," and not to their division superintendents. He thought that the general superintendent would have the time and information needed to coordinate these activities. To illustrate more clearly these lines of authority, McCallum drew up a detailed chart-certainly one of the earliest organization charts in an American business enterprise."