Opinion of the Court. Objections were made by the defendant to these questions, which were sustained, but afterwards, when the witness was again on the stand, the objections were withdrawn, whereupon the plaintiff withdrew all the questions except the one which we have last quoted, and to that the witness answered, "We did not; no, sir." These references are probably sufficient to fully present the questions for consideration. It will not be claimed that it is within the province of this court to review any question as to the admission or rejection of testimony which does not bear directly upon some matter of a Federal nature. It will be noticed that no testimony was ruled out showing, or tending to show, what was in fact valued and assessed by the state board. There was also direct testimony that no franchise belonging to the plaintiff was estimated in making the assessment. The inquiry, therefore, in view of the testimony received and that offered and rejected is narrowed to these two matters: First. If an assessing board, seeking to assess for purposes of taxation a part of a road within a State, the other part of which is in an adjoining State, ascertains the value of the whole line as a single property and then determines the value of that within the State, upon the mileage basis, is that a valuation of property outside of the State, and must the assessing board, in order to keep within the limits of state jurisdiction, treat the part of the road within the State as an independent line, disconnected from the part without, and place upon that property only the value which can be given to it if operated separately from the balance of the road? Second. Where an assessing board is charged with the duty of valuing a certain number of miles of railroad within a State forming part of a line of road running into another State, and assesses those miles of road at their actual cash value determined on a mileage basis, is this placing a burden upon interstate commerce, beyond the power of the State, simply because the value of that railroad as a whole is created partly and perhaps largely by the interstate commerce which it is doing? With regard to the first question, it is assumed that no special circumstances exist to distinguish between the condi Opinion of the Court. tions in the two States, such as terminal facilities of enormous value in one and not in another. With this assumption the first question must be answered in the negative. The true value of a line of railroad is something more than an aggregation of the values of separate parts of it, operated separately. It is the aggregate of those values plus that arising from a connected operation of the whole, and each part of the road contributes not merely the value arising from its independent operation, but its mileage proportion of that flowing from a continuous and connected operation of the whole. This is no denial of the mathematical proposition that the whole is equal to the sum of all its parts, because there is a value created by and resulting from the combined operation of all its parts as one continuous line. This is something which does not exist, and cannot exist, until the combination is formed. A notable illustration of this was in the New York Central Railroad consolidation. Many years ago the distance between Albany and Buffalo was occupied by three or four companies, each operating its own line of road, and together connecting the two cities. The several companies were united and formed the New York Central Railroad Company, which became the owner of the entire line between Albany and Buffalo, and operated it as a single road. Immediately upon the consolidation of these companies, and the operation of the property as a single, connected line of railroad between Albany and Buffalo, the value of the property was recognized in the market as largely in excess of the aggregate of the values of the separate properties. It is unnecessary to enter into any inquiry as to the causes of this. It is enough to notice the fact. Now, when a road runs into two States each State is entitled to consider as within its territorial jurisdiction and subject to the burdens of its taxes what may perhaps not inaccurately be described as the proportionate share of the value flowing from the operation of the entire mileage as a single continuous road. It is not bound to enter upon a disintegration of values and attempt to extract from the total value of the entire property that which would exist if the miles of road within the State were Opinion of the Court. operated separately. Take the case of a railroad running from Columbus, Ohio, to Indianapolis, Indiana. Whatever of value there may be resulting from the continuous operation of that road is partly attributable to the portion of the road in Indiana and partly to that in Ohio, and each State has an equal right to reach after a just proportion of that value, and subject it to its taxing processes. The question is, how can equity be secured between the States, and to that a division of the value of the entire property upon the mileage basis is the legitimate answer. Taking a mileage share of that in Indiana is not taxing property outside of the State. The second question must also be auswered in the negative. It has been again and again said by this court that while no State could impose any tax or burden upon the privilege of doing the business of interstate commerce, yet it had the unquestioned right to place a property tax on the instrumentalities engaged in such commerce. See among many other cases, Marye v. Baltimore & Ohio Railroad, 127 U. S. 117; Pullman's Palace Car Co. v. Pennsylvania, 141 U. S. 18. The rule of property taxation is that the value of the property is the basis of taxation. It does not mean a tax upon the earnings which the property makes, nor for the privilege of using the property, but rests solely upon the value. But the value of property results from the use to which it is put and varies with the profitableness of that use, present and prospective, actual and anticipated. There is no pecuniary value outside of that which results from such use. The amount and profitable character of such use determines the value, and if property is taxed at its actual cash value it is taxed upon something which is created by the uses to which it is put. In the nature of things it is practically impossible at least in respect to railroad property to divide its value, and determine how much is caused by one use to which it is put and how much by another. Take the case before us; it is impossible to disintegrate the value of that portion of the road within Indiana and determine how much of that value springs from its use in doing interstate business, and how much from its use in doing business wholly within the State. An at Opinion of the Court. tempt to do so would be entering upon a mere field of uncertainty and speculation. And because of this fact it is something which an assessing board is not required to attempt. Take for illustration, property whose sole use is for purposes of interstate commerce, such as a bridge over the Ohio between the States of Kentucky and Ohio. From that springs its entire value. Can it be that it is on that account entirely relieved from the burden of state taxation? Will it be said that the taxation must be based simply on the cost, when never was it held that the cost of a thing is the test of its value? Suppose there be two bridges over the Ohio, the cost of the construction of each being the same, one between Cincinnati and Newport, and another twenty miles below and where there is nothing but a small village on either shore. The value of the one will, manifestly, be greater than that of the other, and that excess of value will spring solely from the larger use of the one than of the other. Must an assessing board in either State, assessing that portion of the bridge within the State for purposes of taxation, eliminate all of the value which flows from the use, and place the assessment at only the sum remaining? It is a practical impossibility. Either the property must be declared wholly exempt from state taxation or taxed at its value, irrespective of the causes and uses which have brought about such value. And the uniform ruling of this court, a ruling demanded by the harmonious relations between the States and the national government, has affirmed that the full discharge of no duty entrusted to the latter restrains the former from the exercise of the power of equal taxation upon all private property within its territorial limits. All that has been decided is that, beyond the taxation of property, according to the rule of ordinary property taxation, no State shall attempt to impose the added burden of a license or other tax for the privilege of using, constructing, or operating any bridge, or other instrumentality of interstate commerce, or for the carrying on of such commerce. It is enough for the State that it finds within its borders property which is of a certain value. What has caused that value is immaterial. It is protected by state laws, Syllabus. and the rule of all property taxation is the rule of value, and by that rule property engaged in interstate commerce is controlled the same as property engaged in commerce within the State. Neither is this an attempt to do by indirection what cannot be done directly- that is, to cast a burden on interstate commerce. It comes rather within that large class of state action, like certain police restraints, which, while indirectly affecting, cannot be considered as a regulation of interstate commerce, or a direct burden upon its free exercise. We answer this question, therefore, in the negative. These are the only matters which seem to distinguish this case from the two preceding, and, therefore, the judgment of the Supreme Court of Indiana is Affirmed. MR. JUSTICE HARLAN and MR. JUSTICE BROWN dissented from the opinion and judgment in this case upon the grounds stated in their dissenting opinion in Pittsburgh, Cincinnati, Chicago & St. Louis Railway Company v. Backus, No. 899, ante, 421, 437. MR. JUSTICE JACKSON did not hear the arguments in this case, or take any part in its decision. INTERSTATE COMMERCE COMMISSION v. BRIMSON. APPEAL FROM THE CIRCUIT COURT OF THE UNITED STATES FOR THE NORTHERN DISTRICT OF ILLINOIS. The twelfth section of the Interstate Commerce Act authorizing the Circuit Courts of the United States to use their process in aid of inquiries before the Commission established by that act, is not in conflict with the Constitution of the United States, as imposing on judicial tribunals duties not judicial in their nature. A petition filed under that section in the Circuit Court of the United States against a witness, duly summoued to testify before the Commission, to compel him to testify or to produce books, documents, and papers re |