A Time to Print, a Time to Reform

The public mechanical clock and movable type printing press were arguably the most important and complex technologies of the late medieval period. We document two of their most important, yet unforeseeable, consequences. First, towns that were early adopters of clocks were more likely to also be early adopters of presses. We posit that towns with clocks became upper-tail human capital hubs|both technologies required extensive technical know-how that had many points of overlap. Second, a three-stage instrumental variables analysis indicates that the press in uenced the adoption of Protestantism, while the clock's effect on the Reformation was mostly indirect.