To the Gnat

When by the green-wood side, at summer eye, 
Poetic visions charm my closing eye;
And fairy-scenes, that Fancy loves to weave,
Shift to wild notes of sweetest minstrelsy;
'Tis thine to range in busy quest of prey,
Thy feathery antlers quivering with delight,
Brush from my lids the hues of heaven away,
And all is Solitude, and all is Night!
—Ah now thy barbed shaft, relentless fly,
Unsheaths its terrors in the sultry air!
No guardian sylph, in golden panoply,
Lifts the broad shield, and points the glittering spear. 
Now near and nearer rush thy whirring wings,
Thy dragon-scales still wet with human gore.
Hark, thy shrill horn its fearful larum flings!
—I wake in horror, and dare sleep no more!