Possible Clues:

• ' - - of the Queen's Navee!'
• Drawing instrument found amongst dividers?
• One regretting installing Liberal leader in government
• One in power with regret imprisoning Liberal right
• Royal liner?
• Man who may impose a rigid measure?
• Aid for a straight line
• The measure of one who has control
• One who regrets maybe taking in Liberal leader
• It's often a foot long