Henry Timrod - XI. "Which Are the Clouds, and Which the Mountains? See" lyrics

Which are the clouds, and which the mountains? See, They mix and melt together! Yon blue hill Looks fleeting as the vapors which distill Their dews upon its summit, while the free And far-off clouds, now solid, dark, and still, An aspect wear of calm eternity. Each seems the other, as our fancies will -- The cloud a mount, the mount a cloud, and we Gaze doubtfully. So everywhere on earth, This foothold where we stand with slipping feet, The unsubstantial and substantial meet, And we are fooled until made wise by Time. Is not the obvious lesson something worth, Lady? or have I wov'n an idle rhyme?