Related Clues:

• Dozen for Hercules
• Works up a sweat
• Toils
• Works over a hot stove, e.g.
• Breaks one's back, say
• Grinds
• Works like a dog
• Doesn't do the job easily
• Ancient galley crew
• Emancipation Proclamation subject
• Herculean efforts
• Works a double shift, e.g.
• Galley group
• Works very hard
• Toils away