NOTE: Completed 2012-04-23. Many new vessel entries have resulted from this work, and they will need to be completed when time permits.
Try this, first in /db/coldesp/correspondence, and then in /db/coldesp/:
xquery version "1.0"; declare default element namespace "http://www.tei-c.org/ns/1.0"; for $r in //name[@type='vessel'][not(@key)] return $r
The vessel tags inside the correspondence seem mainly to be for vessels which HAVE write-ups; these should simply be correctly linked with @key. The broader set include vessels which may not have bios yet; bios need to be created, and those vessels linked.