Possible Clues:

• Narrow passageways
• Narrow channels of the sea joining two larger bodies of water
• Great difficulty in getting good hands, you say
• Juan de Fuca and Magellan
• Difficulties in getting good hands, we're told
• Opens up and one gets in with difficulty
• Dover and Gibraltar
• Pressing situation
• ''Dire'' situations
• In difficulties, one jumps up to protect