Twenty Years hence

Twenty years hence my eyes may grow, If not quite dim, yet rather so; Yet yours from others they shall know,             Twenty years hence. Twenty years hence, though it may hap That I be call'd to take a nap In a cool cell where thunder-clap             Was never heard, There breathe but o'er my arch of grass A not too sadly sigh'd 'Alas!' And I shall catch, ere you can pass,             That wingèd word.