In particular, the prisoner’s companions—companions for the prisoner’s moments of solitude—were the genre of solitary confinement. These handbooks can be thought of as the user’s manuals for the solitary cell, guides to making correct use of the physical space and human routines of the penitentiary.
It is a common refrain of survivors of solitary confinement, from the seventeenth century to the twenty-first, that the experience is indescribable. This paper argues that the prisoner’s companions were an attempt to manage that ineffability, reaching for early modern traditions of devotional writing and practice to define, describe, and script the experience of solitary confinement. In this respect, the texts of the penitentiary movement aided the jailer, no less than the jailed, in understanding the carceral apparatus the eighteenth century was creating. The paper concludes by reflecting on solitary confinement as what Bruno Latour called a “black box,” a phenomenon potentially impervious to the historian’s methods, yet necessary to confront.