Although in a few early cases the Supreme Court enforced statutes which gave legal effect to local customs of miners with respect to mining claims on public lands,[61] and to standards adopted by railroads for equipment on railroad cars,[62] it held, in Schechter Poultry Corp. _v._ United States,[63] and Carter _v._ Carter Coal Company[64] that private trade groups could not be empowered to issue binding rules concerning methods of competition or wages and hours of labor. On the other hand, statutes providing that restrictions upon the production or marketing of agricultural commodities shall become operative only upon a favorable vote by a prescribed majority of the persons affected have been upheld.[65] The position of the Court is that such a requirement does not involve any delegation of legislative authority, since Congress has merely placed a restriction upon its own regulation by withholding its operation in a given case unless it is approved upon a referendum.[66] POWER TO GIVE EFFECT TO CONTINGENT LEGISLATION An entirely different problem arises when, instead of directing another department of government to apply a general statute to individual cases, or to supplement it by detailed regulation, Congress commands that a previously enacted statute be revived, suspended or modified, or that a new rule be put into operation, upon the finding of certain facts by an executive or administrative officer. Since the delegated function in such cases is not that of "filling up the details" of a statute, authority for it must be sought elsewhere than in Wayman _v._ Southard and its progeny. It is to be found in an even earlier case--The Brig Aurora[67]--where the revival of a law upon the issuance of a Presidential proclamation was upheld in 1813. After previous restraints on British shipping had lapsed, Congress passed a new law stating that those restrictions should be renewed in the event the President found and proclaimed that France had abandoned certain practices which violated the neutral commerce of the United States. To the objection that this was an invalid delegation of legislative power, the Court answered briefly that "we can see no sufficient reason, why the legislature should not exercise its discretion in reviving the act of March 1st, 1809, either expressly or conditionally, as their judgment should direct."[68] MODIFICATION OF TARIFF LAWS