Seen from one angle, "Drift," the latest book from artist and poet Caroline Bergvall, is a highly unconventional translation of the medieval poem, "The Seafarer". Or, perhaps it's a meditation on the borders of a language. Or, perhaps its a meditation on "thorn," a runic letter that survived in our alphabet until the rise of printing, when it was replaced by "th", but has persisted in Iceland to the present day. But then again, it might be an exploration of the ways in which forced migrations, caused by socio-political unrest, technological change, ecological disaster, or some combination thereof, represent the drift that gives each language its tumultuous character. It's all here in this slender volume.