Possible Clues:

• Cornish tourist came across me, back at the front
• ____ or grockle, Cornish dialect name for a holidaymaker
• First person set up police force, getting local six-footer
• Heraldic charge, also called pismire
• Cornish term for a tourist or visitor
• Pismire kin
• An ant or, to Cornwall residents, a tourist
• In 1803 he was hanged by them for Cockneys assembled
• Colonizing insect
• SW visitor starts to engage mounted police