How do you know that the pilgrim track 

Along the belting zodiac 

Swept by the sun in his seeming rounds 

Is traced by now to the Fishes’ bounds 

And into the Ram, when weeks of cloud 

Have wrapt the sky in a clammy shroud, 

And never as yet a tinct of spring 

Has shown in the Earth’s apparelling; 

 O vespering bird, how do you know, 

 How do you know?

from The Year's Awakening

by Thomas Hardy