Related Clues:
- Strain
- Sweat
- Force
- Effort
- Elbow grease
- Vigorous effort
- Strenuous efforts
- Use of physical energy
- Tire oxen with heavy effort
- Force ten into the tree back there and ten more with the North
- A fort's the sound of them
- Force is needed to get next 'er about ten
- Use force to tire one among the oxen
- Putting effort into somehow shoring up two rivers
- Physical effort