There was a bit of sealing wax with a fingerprint, a brush entangled with strands of hair, and a set of lieutenants’ epaulets.These were among about 350 artifacts that were recently plucked from the sunken crevices and cabins of the H.M.S. Erebus, one of two naval ships that vanished after setting out from England more than 170 years ago in search of a Northwest passage across the Canadian Arctic.