This is the tricky time: no robin is letting go its final note. No bird-voiced youngsters out-of-doors three yards over are dropping summer games for bed. No cricket charts the temperature's decline. No grass leans under Nox's first zephyr. Cat turns its ear, its head from right to left, searching for echoes of descent. Then, presently assured, it turns from orange to gray, cat-trots to its appointments in the night.