As winter descended on Washington in December 1878, the Forty-fifth Congress gathered for what promised to be a hectic third and final session. Emotions ran high. In this era, Congress habitually reserved much of its business for these brief, intense “lame duck” sessions that fell between the election of legislators in November and the adjournment of Congress the following March. Compounding the usual sense of urgency was the startling result of the recent election: the Democratic party had gained control of the Senate and, when the next Congress convened, would control both the Senate and the House for the first time since before the Civil War. Senate Republicans well understood that they had but a few precious months to close ranks and enact legislation on some of the burning issues of the day: civil rights, the currency, the tariff. Yet when the session opened, none of these issues made their way to the floor. Instead, and despite howls of protest from senators eager to move on to what they plainly regarded as more urgent concerns, the Senate assembled on many afternoons for several weeks to debate a completely different matter: a proposed law concerning the rights of inventors. At this critical juncture in American politics, the Senate found itself embroiled in a long and complex discussion of the virtues and deficiencies of the patent system.