The question whether Congress's power to regulate commerce "among the several States" embraced the power to prohibit it furnished the topic of one of the most protracted debates in the entire history of the Constitution's interpretation, a debate the final resolution of which in favor of Congressional power is an event of first importance for the future of American Federalism. The issue was as early as 1841 brought forward by Henry Clay, in an argument before the Court in which he raised the specter of an act of Congress forbidding the interstate slave trade.[487] The debate was concluded ninety-nine years later by the decision in United States _v._ Darby, in which the Fair Labor Standards Act was sustained. The resume of it which is given below is based on judicial opinions, arguments of counsel, and the writings of jurists and political scientists. Much of this material was evoked by efforts of Congress, from about 1905 onward, to stop the shipment interstate of the products of child labor. ACTS OF CONGRESS PROHIBITIVE OF INTERSTATE COMMERCE The earliest such acts were in the nature of quarantine regulations and usually dealt solely with interstate transportation. In 1884 the exportation or shipment in interstate commerce of livestock having any infectious disease was forbidden.[488] In 1903 power was conferred upon the Secretary of Agriculture to establish regulations to prevent the spread of such diseases through foreign or interstate commerce.[489] In 1905 the same official was authorized to lay an absolute embargo or quarantine upon all shipments of cattle from one State to another when the public necessity might demand it.[490] A statute passed in 1905 forbade the transportation in foreign and interstate commerce and the mails of certain varieties of moths, plant lice, and other insect pests injurious to plant crops, trees, and other vegetation.[491] In 1912 a similar exclusion of diseased nursery stock was decreed,[492] while by the same act, and again by an act of 1917,[493] the Secretary of Agriculture was invested with powers of quarantine on interstate commerce for the protection of plant life from disease similar to those above described for the prevention of the spread of animal disease. While the Supreme Court originally held federal quarantine regulations of this sort to be constitutionally inapplicable to intrastate shipments of livestock, on the ground that federal authority extends only to foreign and interstate commerce,[494] this view has today been abandoned. _See_ pp. 248-249. THE LOTTERY CASE