These appeals raise the single question as to whether, in making the 45-cent rate, the Commission acted within or beyond its power. As the statute makes its finding prima facie correct (Cincinnati, H. & D. R. Co. v. Interstate Commerce Commission, 206 U.S. 154, 51 L. ed. 1000, 27 Sup. Ct. Rep. 648), it will be more convenient to consider the case from the standpoint of the carriers, who first insist that the order was void because made without evidence or finding that the 50-cent rate was unreasonable.
There has been no attempt to make an exhaustive statement of the principle involved, but in cases thus far decided, it has been settled that the orders of the Commission are final unless (1) beyond the power which it could constitutionally exercise; or (2) beyond its statutory power; or (3) based upon a mistake of law. But questions of fact may be involved in the determination of questions of law, so that an order, regular on its face, may be set aside if it appears that (4) the rate is so low as to be confiscatory and in violation of the constitutional prohibition against taking property without due process of law; or (5) if the Commission acted so arbitrarily and unjustly as to fix rates contrary to evidence, or without evidence to support it; or (6) if the authority therein involved has been exercised in such an unreasonable manner as to cause it to be within the elementary rule that the substance, and not the shadow, determines the validity of the exercise of the power. Interstate Commerce Commission v. Illinois C. R. Co. 215 U.S. 470, 54 L. ed. 287, 30 Sup. Ct. Rep. 155; Southern P. Co. v. Interstate Commerce Commission, 219 U.S. 433, 55 L. ed. 283, 31 Sup. Ct. Rep. 288; Interstate Commerce Commission v. Northern P. R. Co. 216 U.S. 544, 54 L. ed. 609, 30Sup. Ct. Rep. 417; Interstate Commerce Commission v. Alabama Midland R. Co. 168 U.S. 146, 174, 42 L. ed. 414, 425, 18 Sup. Ct. Rep. 45.
In determining these mixed questions of law and fact, the court confines itself to the ultimate question as to whether the Commission acted within its power. It will not consider the expediency or wisdom of the order, or whether, on like testimony, it would have made a similar ruling. 'The findings of the Commission are made by law prima facie true, and this court has ascribed to them the strength due to the judgments of a tribunal appointed by law and informed by experience.' Illinois C. R. Co. v. Interstate Commerce Commission, 206 U.S. 441, 51 L. ed. 1128, 27 Sup. Ct. Rep. 700. Its conclusion, of course, is subject to review, but, when supported by evidence, is accepted as final; not that its decision, involving, as it does, so many and such vast public interests, can be supported by a mere scintilla of proof, but the courts will not examine the facts further than to determine whether there was substantial evidence to sustain the order.
2. We proceed, then, to a consideration of the carriers' contention that the order was void because made without any testimony that the 50-cent rate of 1907, to St. Paul, was unreasonable. We find that, as far back as 1893, the rate on fir lumber was reduced to 40 cents, on the theory that after a carrier had been paid for transporting a carload of freight from the East to the West, it was better to haul it back loaded with lumber at 40 cents, thereby earning something, than to take it back empty and get nothing. But if, after the empty-car movement had been reversed, the carrier had to be at the expense of hauling cars empty to the West for the purpose of returning them loaded with lumber at the unremunerative rate of 40 cents, there would be a double loss,-it got nothing for hauling the empty car from St. Paul to the coast, and it derived no profit for hauling it back at the low rate. They contend that this situation, in connection with the enormous increase in the cost of operation, not only justified, but required, an advance over the 40-cent rate. And this view of the testimony seems to have been taken by the two commissioners who dissented. If there was no other evidence, the Commission's order could not be sustained.
But these facts do not stand alone. In the first place there was no appeal from the master's finding that: