The history of Arctic exploration is full of cul de sacs, of narrow channels in ice fields, of straits that turn out to be bays, and of illusions that appeared to be opportunities. Some adventurers hesitated and missed breakthroughs of discovery. Others rushed in and found their retreats cut off by enclosing pack ice that ground their ships to flinders. Islands also appeared where none existed: cloudbanks and enormous ice fields masqueraded as solid ground. People saw things that were not there—or that we insist could never have been there.