Answer:
A trail, a union, together tied. Come across me and you will find you cannot change the course I'm on. Without me you cannot travel on. What am I?
In wealth I abound; in water I stand; as a fencer I'm valued all over the land; at Venice I'm famous; by farmers I'm prized; respected by law yet huntsmen despised; consternation and ruin ensue when I break; And the beasts of the forest advantage won't take.
With a halo of water and a tongue of wood; stone as skin long I stood.
Some try to hide some try to cheat. But time will show we always will meet. Try as you might to guess my name. I promise you'll know when you I do claim.
I am a shimmering field that reaches far. Yet I have no tracks and am crossed without paths.
What made Cyclops quit teaching?