"Of course there was a grand outcry at X. Their trade was discriminated against in the worst possible way--so they said--and they complained to the railroad. But the railroad men fell back on the logic of facts. The points were as follows: 1. A whole carload at seventy-five cents would not pay expenses of handling and moving. 2. At higher rates than seventy-five cents they could not get a whole carload, but only half a carload; and half a carload at a dollar rate (the highest charge the article would bear) would not pay expenses. Therefore, 3. On any uniform rate for everybody, the road must lose money, and 4. They would either be compelled to take the oyster car away altogether, or else get what they could at a dollar, and fill up at seventy-five cents. There was no escape from this reasoning; and the oyster men of X chose to pay the higher rate rather than lose the service altogether." The logic of this oyster case seems convincing in its simplicity. But it presents more complications than appear at the outset. [Illustration] First of all, what is the nature of the competition at the more distant point which is alleged to "compel" the lower rate? Is it merely of rival routes or of competing markets? It will be advisable to keep the two distinct so far as possible. Under the first heading, competition of routes, the subjoined sketches represent two possible situations. In both instances, however, Y, enjoying the lower rate, is more distant from Philadelphia than X. The difference between the two arises from the fact that in the one case X is nearer Philadelphia than Y on a roundabout line; while in the other X is actually nearer than Y by the shortest direct route. We may safely assume that the compelling competition alleged at Y as justifying the lower rate is by rail; as, the commodity being a marine bivalve, both places presumably enjoy equal facilities for water carriage. At all events, assuming that we have to do with competing rail routes alone, what differences obtain between the two sets of circumstances above sketched? Not insignificant inequalities in the length or power of the two routes are implied by the diagrams. They are supposed to represent substantially different lines, which may, for the purpose of the argument, be denominated strong, natural, or standard, and weak, unnatural, or abnormal, respectively, so far as the particular traffic in hand is concerned. That this distinction is not irrelevant, but frequently of determinant force, is shown by an analysis of concrete cases which have arisen for adjudication.