It is widely assumed that the Ninth Amendment languished in constitutional obscurity until it was resurrected in Griswold v. Connecticut by Justice Arthur Goldberg. In fact, the Ninth Amendment played a significant role in some of the most important constitutional disputes in our nation's history, including the scope of exclusive versus concurrent federal power, the authority of the federal government to regulate slavery, the constitutionality of the New Deal, and the legitimacy and scope of incorporation of the Bill of Rights into the Fourteenth Amendment. The second of two articles addressing the Lost History of the Ninth Amendment, The Lost Jurisprudence takes a comprehensive look at the Ninth Amendment jurisprudence which flourished from the early nineteenth to the mid-twentieth century. Long assumed never to have received significant attention from the Supreme Court, in fact the first discussion and application of the Ninth Amendment was by none other than Justice Joseph Story himself. In a passage unnoticed since the nineteenth century, Justice Story interpreted and applied the Ninth Amendment precisely the way James Madison and the state ratifying conventions intended; as a rule of construction preserving the retained right of local self-government. Ignored by the framers of the Fourteenth Amendment, the Ninth Amendment and its attendant rule of construction were deployed by courts throughout the nineteenth century to limit the interpretation of federal powers and rights. Ubiquitously paired with the Tenth Amendment, the Ninth suffered the same fate as the Tenth at the time of the New Deal, when both were rendered mere truisms in the face of expansive constructions of federal power. By 1965, the Ninth was assumed to exist in a doctrinal and historical vacuum, an assumption that no one has questioned until now.