that industry should take care of its human wastage, whether that is due to accident or age. That view cannot be dismissed as arbitrary or capricious. It is a reasoned conviction based upon abundant experience. The expression of that conviction in law is regulation. When expressed in the government of interstate carriers, with respect to their employees likewise engaged in interstate commerce, it is a regulation of that commerce. As such, so far as the subject matter is concerned, the commerce clause should be held applicable."[414] Under subsequent legislation, an excise is levied on interstate carriers and their employees, while by separate but parallel legislation a fund is created in the Treasury out of which pensions are paid along the lines of the original plan. The constitutionality of this scheme appears to be taken for granted in Railroad Retirement Board _v._ Duquesne Warehouse Company.[415] BILLS OF LADING; THE FERGER CASE Some years earlier the Court had had occasion in United States _v._ Ferger,[416] decided in 1919, to reiterate the rule laid down in the Southern Railway Case, that Congress's protective power over interstate commerce reaches all kinds of obstructions whatever the source of their origin. Ferger and associates had been indicted under a federal statute for issuing a false bill of lading, to cover a fictitious shipment in interstate commerce. Their defense was that, since there could be no commerce in a fraudulent bill of lading, therefore Congress's power could not reach their alleged offense, a contention which Chief Justice White, speaking for the Court, answered thus: "But this mistakenly assumes that the power of Congress is to be necessarily tested by the intrinsic existence of commerce in the particular subject dealt with, instead of by the relation of that subject to commerce and its effect upon it. We say mistakenly assumes, because we think it clear that if the proposition were sustained it would destroy the power of Congress to regulate, as obviously that power, if it is to exist, must include the authority to deal with obstructions to interstate commerce (_In re Debs_, 158 U.S. 564) and with a host of other acts which, because of their relation to and influence upon interstate commerce, come within the power of Congress to regulate, although they are not interstate commerce in and of themselves. * * * That as instrumentalities of interstate commerce, bills of lading are the efficient means of credit resorted to for the purpose of securing and fructifying the flow of a vast volume of interstate commerce upon which the commercial intercourse of the country, both domestic and foreign, largely depends, is a matter of common knowledge as to the course of business of which we may take judicial notice. Indeed, that such bills of lading and the faith and credit given to their genuineness and the value they represent are the producing and sustaining causes of the enormous number of transactions