AT THE CONCLUSION OF Mason & Dixon's thirty-second chapter, Jeremiah Dixon receives a letter from his long-time mentor, William Emerson, who has entrusted Dixon with a watch of perpetual motion that never requires winding. Dixon has written to Emerson to report that the watch was swallowed by R.C., a member of the surveying party, and Emerson's reply bears the challenging post-script, “Time is the Space that may not be seen. —” (326). This essay reads Mason & Dixon as a literary attempt, not to render time visible, but to produce meaning from time itself. As such, Thomas Pynchon incorporates temporality into the narrative's production, not only writing about the historical interface between the eighteenth and twentieth centuries, but also performing the historicity of that interface. To make meaning from time's perpetual motion, Pynchon employs a temporally parallactic narrative form (different narrators deliver the story from ostensibly different moments in time) that effects, for the reader, a semblance of experiential time. These narrative tricks superimpose linear and cyclical models of time into one textual form, and they allow Pynchon to write about time without sacrificing, by spatializing, time's temporality or history's historicity.