"The true value of a line of railroad is something more than an aggregation of the values of the 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.... The value of property results from the use to which it is put, and varies with the profitableness of that use, past, present and prospective, actual and anticipated. There is no pecuniary value outside that which results from such use.... "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 the State of 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 attempt to do so would be entering upon a mere field of uncertainty and speculation." In the Michigan cases, the principal one being Michigan Central Railroad _vs._ Powers (201 U. S., 245), the question of method of valuation was not passed on by the Courts for the reason that, after the evidence was in, and during the argument, counsel for the railroad admitted that the Cooley valuation was as correct a figure as it was possible to secure under then existing conditions, methods and rates of taxation being the issue. It is thus seen that the Supreme Court of the United States was not, in any of the earlier cases, required to pass squarely on the propriety of any method of arriving at a "fair value," and consequently had not, prior to 1909, defined any hard-and-fast rules of procedure in determining such value. The Circuit Courts have passed on kindred questions in a few cases, among which San Diego Land and Town Company _vs._ National City (74 Fed., 83), and San Diego Land and Town Company _vs._ Jasper (110 Fed., 714) hold as above, and cite most of the cases referred to. In the latter case the Court says: "The actual value of such property obviously depends upon a variety of considerations—among them the actual and prospective number of consumers—and is no more unchangeable than the value of any other kind of property." As an illustration, there is cited the effect of a year's drouth on an irrigation plant as temporarily affecting the value of property. In the case of Cotting _vs._ Kansas City Stock Yards (82 Fed., 839) the Circuit Court touches on one very interesting argument, in the light of some of the methods of valuation advocated by railway managers and some of the criticisms of recent valuation work.