“Far Company” by W.S. Merwin

At times now from some margin of the day
I can hear birds of another country
not the whole song but a brief phrase of it
out of a music that I may have heard
once in a moment I appear to have
forgotten for the most part that full day
no sight of which I can remember now
though it must have been where my eyes were then
that knew it as the present while I thought
of somewhere else without noticing that
singing when it was there and still went on
whether or not I noticed now it falls
silent when I listen and leaves the day
and flies before it to be heard again
somewhere ahead when I have forgotten