2. In the present case the motion to dismiss for want of jurisdiction was made at the end of the trial and was based, not upon the pleadings, but upon the evidence. It becomes necessary, therefore, to make a statement of the facts material to that issue:-The plaintiff, the Mitchell Coal and Coke Company, owned six coal mines in the Clearfield District, and between 1897 and May 1, 1901, shipped its products over the Pennsylvania Railroad in state and interstate commerce. During that time the provisions of the Commerce Act were constantly violated and there were many instances in which the carrier gave secret rates to shippers from whom it collected the full tariff and subsequently refunded the difference between the legal and the illegal rate. Many such rebates were paid to the plaintiff, the Mitchell Company, which in this case claimed the right to recover, as damages, the difference between these rebates paid to it and what it claimed were the additional rebates paid to the Altoona and other companies mentioned in the declaration. The Referee found that, for a part of the time, 70 per cent. of plaintiff's shipments had been made at secret rates, and held, citing Pa. R. R. v. International Co., 173 Fed. Rep. 1, 9, that, as to this tonnage, the plaintiff was as much a violator of the statute as was the carrier and that no cause of action arising out of this illegal contract would be enforced by the courts. He therefore limited the inquiry to a consideration of the damages in respect to that part of the plaintiff's shipments on which no rebates had been paid.

From the Referee's report, and the testimony returned therewith, it appears that Clearfield District is the name given to a large coal field reached by the lines of the Pennsylvania Railroad. In this district there were many mines-some near the railroad and others at considerable distances therefrom, but all reached by lateral lines or spur tracks, over which cars were carried to and from the

mines. This Clearfield District was treated as a single shipping station, and the rates from all points therein were the same where coal was transported to the same point beyond the State. The published tariff named the rate from station to destination, but it was uniformly construed to include the haul from the mine. The published rate was so applied on all shipments made by the plaintiff as well as on those made by the Altoona and other companies named in the complaint.

It further appeared that to these companies the carrier paid what is called a trackage or lateral allowance, claiming that it was compensation allowed them for hauling cars from their mines to the station. The defendant's contention that there was no concealment of these payments is controverted by the plaintiff, which insists that it had no knowledge of such payments until 1898, when its officers were informed that the railway was paying some companies 10 cents a ton for such services. The Mitchell Company, the plaintiff, thereupon bought an engine to be used for that purpose at its Gallitzin mine and with this engine hauled cars, loaded and empty, between that mine and the station. For this work it demanded that the defendant should pay the same lateral allowance of 10 cents a ton that the railroad paid other companies for similar services. The carrier contended that it was itself prepared to do the switching at the Gallitzin mine, though, on account of dissimilarity of conditions, it could not economically do so at the Altoona and other mines referred to in the complaint. It therefore declined to pay a lateral allowance to the plaintiff, but offered to continue to treat this haul as included in the rate and to do that work without extra charge to the Mitchell Company. The plaintiff then offered to do the hauling for less than 10 cents, the exact amount not appearing. The proposition having been declined in 1899, the plaintiff, on November 20, 1905, brought this suit, offering evidence to show that in some

cases the allowance was as high as 18 cents a ton instead of 10 cents, as it had previously understood.

In addition to the Gallitzin mine, the plaintiff owned five others in the Clearfield District. They were located at points from 1,100 to 3,000 feet from the railroad and were reached by spur tracks belonging to the plaintiff, over which cars were hauled by the locomotives belonging to the Pennsylvania Railroad. For this service the carrier made no extra charge, treating it as included in the rate, though the tariff published the rate as from station to destination.

The mines of the Altoona, Glen White and Millwood Companies were located in the Clearfield District, while those of the Latrobe and Bolivar Companies were near by in the Latrobe District.

The Millwood was reached by a narrow gauge track, over which cars were hauled by that coal company's narrow gauge engines. For doing that work it was paid a lateral allowance of 15 cents a ton until April, 1899, and after that date 10 cents a ton.

The Glen White mine was about three miles from the main road and was reached by a spur having light rails, steep grades and sharp curves, over which the evidence tended to show that the engines of the railroad could not be safely or economically operated. This company transported the coal cars with its own engine and for doing that work the defendant paid it a lateral allowance of 15 cents a ton. On December 28, 1901 (subsequent to the transactions involved in this litigation), the carrier gave notice that it would discontinue lateral allowances on coke, but would allow 15 cents per ton on coal.

The Altoona mine was reached by a spur track, over which, with its own engines, the Altoona Company hauled cars and was paid a lateral allowance of 13 cents on coal and 10 cents on coke to points on the Hollidaysburg Branch, and 18 cents on coal and 20 cents on coke to

points east of Altoona. On December 28, 1901, this lateral allowance on coal was discontinued and that on coke reduced to 12 cents a ton. On January 1, 1902, all lateral allowances were discontinued.

Inasmuch as the payments to the Altoona were larger than those to any other coal company, the plaintiff claimed that they were the legal measure by which damages were to be assessed. The evidence was therefore specially directed to the situation at this mine, which was a little over three miles in an air line from the railroad and eight hundred feet above the station level. The grade was, not only very steep, but it was necessary to make use of three switchbacks in order to reach the elevation of the mine. The line was thus lengthened so as to be about 5 miles in length. The curves on this track were very sharp; the rails were light, and only specially constructed engines could be used. There was evidence that before the Pennsylvania's locomotives could have been operated over this spur it would have been necessary to put in heavy rails, strengthen the culverts and realign the track. Owing to the steep grade only four cars could be hauled at a time, and it required from three to six times as long to do the same amount of transportation work as at the Gallitzin mine.

3. The plaintiff insists that these facts demonstrate that the payments to the Altoona and other companies were not measured by the value of the track or locomotive, or by the cost of the service rendered, but were unreasonable in amount, were arbitrarily fixed, lowered or withdrawn and constituted a mere cover for rebating. On the other hand, the defendant insisted that, though bound to haul the cars to and from the mines, it could not economically do the work on account of the physical conditions at the Altoona, Millwood and Glen White mines and that it, therefore, employed those companies to perform that transportation service, paying them therefor an allowance

which is prima facie reasonable and must be so treated by the courts until the Commission has determined that it was excessive or constituted an unjust discrimination.

On this hearing, involving a matter of jurisdiction, we cannot pass upon these questions which go to the merits of the controversy. But these claims of the parties emphasize the fact that there are two classes of acts which may form the basis of a suit for damages. In one the legal quality of the practice complained of may not be definitely fixed by the statute so that an allowance, otherwise permissible, is lawful or unlawful, according as it is reasonable or unreasonable. But to determine that question involves a consideration and comparison of many and various facts and calls for the exercise of the discretion of the rate-regulating tribunal. The courts have not been given jurisdiction to fix rates or practices in direct proceedings, nor can they do so collaterally during the progress of a lawsuit when the action is based on the claim that unreasonable allowances have been paid. If the decision of such questions was committed to different courts with different juries the results would not only vary in degree, but might often be opposite in character-to the destruction of the uniformity in rate and practice which was the cardinal object of the statute.

4. The necessity under the statute of having such questions settled by a single tribunal in order to secure singleness of practice and uniformity of rate has been pointed out and settled in the Abilene, Pitcairn and Robinson Cases and is referred to here because this record and that in Pennsylvania R. R. v. International Co., ante, p. 184, just decided, furnish a striking illustration of the results which would follow if the reasonableness of an allowance could be decided by different tribunals. Both cases involve the payment of 18 cents a ton to the Altoona Company during the same period and for identically the same reasons. In both the plaintiff insisted that the payment