This proposition is clear beyond dispute. The actual cost of service, which fixes an irreducible minimum rate between Y and Philadelphia, is less on the short line than by the roundabout one. For either road to accept less than the portion of the cost traceable to this particular traffic, that is to say, the extra cost incident to its acceptance, is economically inconceivable. From this it follows, other conditions being equal, that the shortest line between Y and Philadelphia rules the rate in the last instance. This is normally the case. The roundabout route thereafter merely accepts the rate thus compelled. To permit the roundabout line to rule the minimum rate would not only violate a fundamental principle of operation: it would inevitably lead to chaos. The analogy with cut-throat competition in business is obvious. It is equally plain that the mere acceptance of a short line rate by a roundabout road, so long as this rate is adequate to yield some profit over the extra cost, while of advantage to some, may not work positive injury to any one. This condition normally corresponds to the state of affairs represented by diagram A. The nearer point, X, as Hadley avers, has no just grievance against Y because the latter has the good fortune to have a direct service to Philadelphia at a low rate. For Y to withdraw shipments from the line via X might even destroy the only chance of X for a market. It would also deprive Y of whatever benefit it might have derived from competition either of routes or of facilities. Of course, we have expressly omitted market competition as a factor, reserving it for separate treatment. Yet one objection arises. Normally, the direct line ought to maintain a tariff conforming in some degree to the distance principle. The roundabout line can compete at Y only by a violation of it, unless, indeed, its local tariffs be graded much more gradually. In other words, its progression towards the maximum must be distributed over a much longer line. Even this would, on Hadley's statement of fact, eliminate X from the Philadelphia market. Such reduction of local rates upon the roundabout route would in turn discriminate against places like Z on the direct line, equally distant with X from Philadelphia. For the latter places would necessarily be assessed at a higher rate per ton-mile.[203] This would constitute another form of local discrimination, which will be discussed in due time. There is, therefore, at best, only a choice of adjustments, either of which leads to some form of inequality. But, upon the whole, balancing the evil with the good, the first variant of our oyster case appears to be best solved by according all shippers at Y a somewhat lower rate than X enjoys.